CHEMISTRY

Hence, Fe is in only + 3 oxidation state in 5. Which one of the following

2019 (II) Fe 2O 3, whereas in rest of the species, the statements about diamond and
same metal exhibits different oxidation
graphite is not correct?
states.
1. Let there be an object having (a) Diamond has a tetrahedral
some chemicals in it. It starts 3. Which one of the following structure, whereas graphite has a
moving with a uniform velocity statements about glass is not hexagonal planar structure.
v and a chemical reaction starts correct? (b) Both physical and chemical
happening. In this case, which (a) Glass is often said to be a properties of diamond and
graphite are different.
of the following statement(s) supercooled liquid.
(b) Glass has no definite melting point. (c) Graphite is soft, but diamond is
is/are correct? hard.
(c) Soda glass is harder than pyrex
1. Chemical reactions happening (d) Graphite is a good conductor of
glass.
in the system cannot change (d) Boron is present in pyrex glass. electricity, while diamond is not.
the velocity (v) of the centre
_ (c) Pyrex glass is harder than soda lime _ (b) Statement given in option (b) is
of mass of the object. incorrect. The correct statement is, the
glass. This is because, pyrex glass,
2. Chemical reactions happening (a particular blend of borosilicate glass) physical properties of both diamond
in the system cannot change has a higher proportion of silicone dioxide and graphite are same. But, as the both
than soda lime glass. Due to which, pyrex diamond and graphite are allotropes of
kinetic energy of the particles same element (carbon).
inside with respect to the glass does not expand on heating, while
soda lime glass is not likely to be directly Thus, they both exhibits similar
centre of mass of object. and strongly heated. chemical properties.
Select the correct answer using Thus, the high heating tolerance of pyrex So, option (b) is the correct answer.
the code given below: glass makes it harder than soda lime glass. 6. The raw materials used for the
(a) Only 1 (b) Only 2 Hence, option (c) is incorrect. manufacture of Portland
(c) Both 1 and 2 (d) Neither 1 nor 2
Rest of the given statements are correct. cement are
_ (a) A chemical reaction is an internal 4. Which one of the following (a) lime, silica and sulphur dioxide
process, so there is no change in (b) lime, silica and carbon dioxide
momentum and mass (since, mass is statements is correct?
(c) lime, silica and alumina
conserved in a chemical reaction). (a) Both boiling and evaporation are
(d) lime, silica and boric acid
But in a chemical reaction, the kinetic surface phenomena.
energy of the particle is changes with (b) Boiling is a surface phenomenon, but _ (c) The raw materials used for the
respect to centre of mass of whole body. evaporation is a bulk phenomenon. manufacture of Portland cement are
Hence, statement 1 is correct statement (c) Both boiling and evaporation are bulk lime, clay (provides alumina and silica)
phenomena. and gypsum.
2 is incorrect.
(d) Boiling is a bulk phenomenon, but Thus, the correct option is (c).
2. Which one of the following evaporation is a surface
compounds does not exhibit a 7. Which one of the following
phenomenon. statements about water is not
different oxidation number of
the same element? _ (d) Boiling is a bulk phenomenon, but true?
evaporation is a surface phenomenon is (a) Hydrogen bonds are present in
(a) Pb 3O 4 (b) Fe 3O 4 (c) Fe 2O 3 (d) Mn3O 4 the correct statement. This is because, liquid water.
_ (c) Among the given species/ during evaporation, the high energy (b) Water has a high boiling point.
compounds, only Fe 2O 3 does not exhibit molecules from the liquid go into the (c) Water has a high heat of fusion.
different oxidation number of Fe, in this gaseous phase only through the surface. (d) Water is a non-polar molecule.
species can be calculated as : While, in boiling, the vaporisation occurs
Let x be the O.N. of Fe. throughout the bulk of the liquid and the _ (d) The option (d) contains incorrect
vapours expand freely into the statement. Water is a polar molecule in
∴ 2 x + 3( − 2 ) = 0 which central oxygen atom is
surrounding.
x =+ 3 sp3-hybridised.
 °
Out of four sp3-hybrid orbit, two for _ (c) The net movement of water from a Zn has highly negative Ered value, while
σ bond with H-atom and rest two are dilute to concentrated solution through a °
Cu has least negative Ered value.
occupied by lone pair of electrons. selectively permeable membrane is
called osmosis. This term is used Thus, the correct order is
Thus, due to V-shaped structure
of H 2O is a polar molecule (µ = 1840). specifically to refers to the diffusions of Zn > Cu > Ag
water across semi or selectively
8. A sample of ‘soft soap’ contains permeable membrane.
(a) caesium (b) potassium Water moves from a region of higher 2019 (I)
(c) calcium (d) magnesium concentration to a region of lower
concentration until an equilibrium is
_ (b) Soaps are the sodium or potassium reached. 17. Which one of the following
salts of long chain fatty acid (RCOONa).
energy is stored in the links
e.g. stearic acid (C 17H 35COOH), oleic 13. Which one of the following
acid (C 17H 33COOH) and palmitic acid
between the atoms?
statements regarding cathode (a) Nuclear energy
(C 15H 31COOH).
rays is not correct? (b) Chemical energy
Therefore, a sample of soft soap
(a) Cathode ray particles are electrons. (c) Potential energy
contains sodium or potassium.
(b) Cathode ray particles start from (d) Thermal energy
Thus, the option (b) is correct. anode and move towards cathode.
9. Which one of the following does (c) In the absence of electrical and _ (b) Chemical energy is stored in the
bonds of atoms and molecules.
not represent the salt, calcium magnetic fields, cathode rays travel
Nuclear energy is stored in the nucleus
in straight lines.
carbonate? of an atom.
(d) Television picture tubes are cathode Potential energy is the energy of
(a) Lime water (b) Limestone
ray tubes. position or gravitational potential energy.
(c) Chalk (d) Marble
_ (b) Cathode rays start from cathode and Thermal energy or heat is the vibration
_ (a) Calcium carbonate is also known as move towards anode, because they are or movement of atoms and molecules in
limestone and has a molecular formula is made of negatively charged electrons. substances.
CaCO 3. It is found in nature in the form of Hence, option (b) is incorrect statement.
chalk, marble etc. Thus, limestone. chalk 18. Which one of the following
and marble represents calcium 14. A very large volume of hydrogen minerals is used as a fuel in
carbonate. can be accommodated by making nuclear power stations?
Whereas, lime water is the aqueous (a) non-metallic hydrides (a) Bauxite (b) Quartz
solution of Ca(OH)2. (b) hydrogen peroxide (c) Feldspar (d) Pitch-blende
Thus, the correct option is (a). (c) non-stoichiometric hydrides
(d) alkali metal hydrides _ (d) Pitch-blende is a radioactive uranium
10. Which one of the following rich mineral which is used as a fuel in
substances is not a mixture? _ (c) A very large volume of hydrogen can nuclear power stations.
(a) Tin (b) Sea water be accommodated by making It has a chemical composition that is
non-stoichiometric hydrides. largely UO 2, but also contains UO 3 and
(c) Soil (d) Air
Such hydrides are formed by some of oxides of lead, thorium and rare earth
_ (a) A mixture is a type of matter which the metals (e.g. Pd, Pt). elements.
has variable composition throughout. This property of hydrogen has high
Among the given options, only Sn(tin) is potential for hydrogen storage . 19. Which one of the following is
not a mixture, while rest are the not a synthetic detergent?
examples of mixture. Sn is an element 15. Which one of the following is (a) CH 3(CH 2 )10CH 2OSO 3−Na +

which contains only one kind of particles not a monoatomic element? (b)[CH 3(CH 2 )15 N (CH 3 )3 ] + Br −
or atoms. (a) Copper (b) Helium
(c) Iodine (d) Barium (c) CH 3(CH 2 )16COO −Na +

11. Which one of the following is (d) CH 3(CH 2 )16COO(CH 2CH 2O)n ⋅
termed as ‘dry ice’? _ (c) Among the given species, only iodine CH 2CH 2OH
(a) Ice present in ice-cream is not a monoatomic element. It exists in
(b) Solid water at Antarctica
the form of I 2 (diatomic), while rest occur _ (d) Synthetic detergents are chemically
as monoatomic element. alkyl sulphate or sulphonate or
(c) Solid state of carbon dioxide
(d) Solid water of ionosphere ammonium salt of long chain fatty acids.
16. Which one of the following
Thus, CH 3(CH 2 )16COO(CH 2CH 2O)n ⋅
_ (c) When liquefied CO 2 is allowed to represents the correct order of CH 2CH 2OH, option (d) is not a synthetic
expand rapidly, it gets converted in the electron releasing tendency of detergent, while the remaining options
form of solid CO 2 which is also called metals? contain synthetic detergents.
dry ice. Thus, dry ice is solid state of the (a) Zn > Cu > Ag (b) Ag > Cu > Zn
carbon dioxide. (c) Cu > Zn > Ag (d) Cu > Ag > Zn 20. Which one of the following is an
example of a clean fuel?
12. Net movement of water from a _ (a) The correct order of electron (a) Coke (b) Propane
dilute to a concentrated solution releasing tendency of given metals is
(c) Petrol (d) Wax
through a selectively permeable Zn> Cu > Ag.
membrane is called This can be explained on the basis of _ (b) Clean fuels are fuels that have a
standard reduction potentials of given lower carbon intensity than the standard
(a) Diffusion (b) Dispersion ° for the fuel it replaces. Examples of clean
(c) Osmosis (d) Absorption elements. More negative be the Ered
value, greater is the tendency of fuels include ethanol, biodiesel, natural
element to release electron. gas, biogas, propane and hydrogen.
21. Which one of the following metals _ (d) Iron (Fe) is a chemical element with by the formation of nitrogen-oxygen
does not react with cold water? atomic number 26. It is a metal that (N == O) double bond.
belongs to the first transition series and Thus, they do not react with each other.
(a) Calcium (Ca) (b) Potassium (K)
(c) Magnesium (Mg) (d) Sodium (Na) group 8 of the periodic table.
Its melting point is 1538°C (~1500°C)
29. The equivalent weight of oxalic
_ (c) Magnesium (Mg) does not react with or 1811 K. acid in C 2H2O 4 ⋅ 2H2O is
cold water, but reacts with hot water, (a) 45 (b) 63
Mg + 2H 2O → Mg(OH)2 + H 2 ↑
26. Which one of the following
statements is not correct for the (c) 90 (d) 126
Mg + H 2O → MgO + H 2 ↑
given reaction? _ (b) Equivalent weight of an acid
On the other hand, calcium (Ca),
Fe(s) + CuSO4 (aq) → FeSO4 (aq) =
Molecular weight
potassium (K) and sodium (Na) are react
with cold water. + Cu(s) Basicity
Thus, option (c) is correct. (a) Iron is the reducing agent Molecular weight of C 2H 2O 4 ⋅ 2H 2O
(b) The solution turns green in colour = 2 × 12 + 2 × 1 + 4 × 16 + 2 × 18 = 126
22. In which of the following pairs after the reaction ∴ Equivalent weight of C 2H 2O 4 ⋅ 2H 2O
are the isoelectronic ions? (c) Copper is a more reactive metal than 126
(a) Mg 2 + , Ar (b) Na + , O 2− = = 63
iron 2
(c) Al 3 + , Cl − (d) K + , Ne (d) The reaction is an example of a
redox reaction 30. On exposure to moist air, copper
_ (b) According to question, gains a green coat on its surface
_ (c) A more reactive metal displaces a due to formation of which one
Atomic Number of less reactive metal from its solution.
Ion of the following compounds?
Number Electrons Fe( s ) + CuSO 4 ( aq ) → FeSO 4 ( aq )
Mg 2 + 12 12 − 2 = 10 +Cu( s ) (a) Copper carbonate
(b) Copper oxide
Ar 18 18 In the above given reaction, iron (Fe)
displaces copper (Cu) from its solution (c) Copper sulphate
Na + 11 11 − 1 = 10 (d) Copper nitrate
(CuSO 4 ), thus copper is less reactive
O 2− 8 8 + 2 = 10 than iron. _ (a) On exposure to moist air, copper
Al 3 + 13 13 − 3 = 10 Therefore, option (c) is incorrect, while gains a green coat on its surface due to
− the remaining options are correct. formation of copper carbonate.
Cl 17 17 + 1 = 18
2Cu (s) + CO2(g) + O2 (g) + 2H2O(l)
K+ 19 19 − 1 = 18 27. Which one of the following is an Copper
from moist air
Ne 10 10 organic acid?
(a) Hydrochloric acid → 2CuCO3·Cu(OH)2
The species containing same number of Basic copper carbonate
(b) Nitric acid
electrons are isoelectronic. Thus, Na + (green coating)
(c) Acetic acid
and O 2− are isoelectronic species.
Hence, option (b) is correct. (d) Sulphuric acid
31. Which one of the following will
23. Which one of the following is _ (c) An organic acid is an organic not produce carbon dioxide on
compound with acidic properties. The reacting with an aqueous
used as a binder in paints? most common organic acids are the
(a) Titanium dioxide (b) Novolac carboxylic acids. Among the given solution of hydrochloric acid?
(c) Phthalocyanine (d) Silicones options, acetic acid (CH 3COOH) is an (a) Limestone (b) Quicklime
organic acid. The remaining options (c) Chalk (d) Marble
_ (d) Binder refers to the substances that contains inorganic acids.
hold the particles of pigment together in _ (b) Calcium carbonate occurs in nature
paints. 28. Dinitrogen (N2 ) and dioxygen in several form like limestone,chalk,
Silicones are used as a binder in paints. (O 2 ) are the main constituents marble, etc. It reacts with aqueous
They are synthetic organo-silicon polymers solution of hydrochloric acid (HCl) to
of air, but they do not react with liberate carbon dioxide.
containing repeated R 2SiO units. each other to form oxides of
CaCO 3 + 2HCl → CaCl 2 + H 2O
24. Basic scientific principle behind nitrogen because,
+ CO 2 ↑
a nuclear reactor is (a) the reaction requires initiation by a
catalyst Quicklime on reaction with HCl does not
(a) nuclear fusion
(b) oxides of nitrogen are unstable liberate CO 2.
(b) controlled nuclear fusion
(c) uncontrolled nuclear fission (c) the reaction is endothermic and CaO + 2HCl → CaCl 2 + H 2O
Quicklime
(d) controlled nuclear fission requires very high temperature
(d) the stoichiometry of N 2 and O 2 in air is 32. Which one of the following
_ (d) Basic scientific principle behind a not ideal for the reaction to take place substances is not a mixture?
nuclear reactor is controlled nuclear
(a) Ice (b) Ice-cream
fission, in which a heavy atomic nucleus _ (c) The reaction of dinitrogen (N 2) and (c) Air (d) Honey
splits into two smaller nuclei and a large dioxygen (O 2) is endothermic and
amount of energy is released in this requires very high temperature. _ (a) Mixtures are obtained by mixing two
process. N 2 + O 2 —→ 2NO or more substances in any proportions.
Thus, among the given options, ice is not
25. Which one of the following could It is because, the nitrogen-nitrogen triple
a mixture as it contains only water
be the melting point of iron? bond (N ≡≡ N) is very strong.
(liquid).
(a) 25°C (b) 37°C The energy cost to break that bond as
The other substances, i.e. ice-cream, air
(c) 500°C (d) 1500°C well as the O == O is not compensated
and honey are mixtures.
33. Tooth enamel is made up of ∴Average atomic mass of oxygen in the 40. Which one of the following is a
75 25
which one of the following sample = 16 × + 18 × = 16 . 5 u tribasic acid?
calcium compounds? 100 100
(a) Hydrochloric acid (b) Nitric acid
(a) Calcium carbonate 36. Which one of the following is a (c) Sulphuric acid
(b) Calcium sulphate heterogeneous mixture? (d) Phosphoric acid
(c) Calcium hydroxide (a) Hydrochloric acid _ (d) H 3PO 4 , phosphoric acid can be
(d) Calcium phosphate (b) Vinegar written as O == P(OH)3. It has three
_ (d) Enamel is the hardest substance in (c) Milk acidic hydrogens (attached to oxygen)
the human body. It contains the highest (d) Soda water and is, therefore tribasic acid.
percentage of minerals, 96% with water
and organic material composing the rest. _ (c) A mixture that does not have uniform On the other hand, hydrochloric acid,
composition is called heterogeneous nitric acid are monobasic, while sulphuric
The primary mineral present in enamel is mixture. acid is dibasic.
hydroxyapatite which is a crystalline
calcium phosphate. Out of the given compounds, milk is a
heterogeneous mixture of fats, 41. Which one of the following
carbohydrates, proteins etc. dispersed statements is not correct?
2018 (II) in water. (a) All carbons in diamond are linked
by carbon-carbon single bond
37. What is the formula mass of (b) Graphite is layered structure in
34. The atomic number of an anhydrous sodium carbonate? which layers are held together by
element is 8. How many (Given, that the atomic masses weak van der Waals’ forces
electrons will it gain to form a of sodium, carbon and oxygen (c) Graphite layers are formed by
compound with sodium? are 23u, 12u and 16u hexagonal rings of carbon atoms
(a) One (b) Two (c) Three (d) Four respectively). (d) Graphite layers are held together by
(a) 286 u (b) 106 u carbon-carbon single bond
_ (b) The atomic number of an element = 8
K L
(c) 83 u (d) 53 u _ (d) Graphite layers are held together by
Electronic configuration = van der Waals’ forces and not by
2 6 _ (b) Chemical formula of (anhydrous) carbon-carbon single bond.
sodium carbonate = Na 2CO 3
∴Valency = 8 − 6 = 2 Hence, statement given in option (d) is
Sodium (atomic number 11) has ∴ Formula unit mass of Na 2CO 3
incorrect.
electronic configuration = (2 × 23 + 12 + 16 × 3) u = 106 u
K L M 42. Which one of the following
= 38. Which one of the following is
2 8 1 solution will have pH less than 7?
called ‘syn gas’?
∴Valency = 1 (a) NaOH (b) KCl (c) FeCl 3 (d) NaCl
(a) C ( s ) + H 2O( g )
Thus, the given element will gain 2
electrons from two sodium atoms to (b) CO( g ) + H 2O( g ) _ (c) FeCl 3 is a salt of strong acid (HCl)
complete its octet. (c) CO( g ) + H 2( g ) and weak base Fe(OH) 3. As a result,
(d) NO 2( g ) + H 2( g ) FeCl 3 is an acidic salt and hence in
Formula of the compound,
solution form its pH lies below 7.
= Na O _ (c) Syn gas or synthesis gas is a mixture
of carbon monoxide (CO) gas and 43. Which one of the following is an
1 2 hydrogen (H 2) gas. It may also consist of oxidation-reduction reaction?
= Na2O carbon dioxide (CO 2) gas. (a) NaOH + HCI → NaCI + H 2O
39. Which one of the following (b) CaO + H 2O → Ca(OH) 2
35. A sample of oxygen contains two
(c) 2Mg + O 2 → 2MgO
isotopes of oxygen with masses reactions will give NO (nitric
(d) Na 2SO 4 + BaCI 2 → BaSO 4
16u and 18u respectively. The oxide) gas as one of the products?
+ 2NaCI
proportion of these isotopes in (a) 3Cu + 8HNO 3 (dil.) → +1 −1 +1 − 1 +1 −1 +1 −2
the sample is 3 : 1. What will be (b) Cu + 4HNO 3 (conc.) → _ (c) (a) Na OH + HCl → Na Cl + H 2 O
the average atomic mass of (c) 4Zn + 10HNO 3 (dil.) → (No change in oxidation states)
+2 − 2 +1 − 2 +2 + 2 − 1
oxygen in this sample? (d) Zn + 4HNO 3 (conc.) → (b) CaO + H 2O → Ca (OH)2
(a) 17.5 u (b) 17 u (c) 16 u (d) 16.5 u
_ (a) (a) 3Cu + 8HNO 3 → 3Cu(NO 3 )2 (No change in oxidation states)
(dil. )
_ (d) Average atomic mass of an element + 2NO ↑ + 4H 2O
(c) Oxidation
Atomic mass of isotope I
(b) Cu + 4HNO 3 → Cu(NO 3 )2 0 0 +2 –2
× % age of isotope I 2Mg + O2 2 MgO
= (conc. )
+ 2NO 2 ↑ +2H 2O
100 Reduction
Atomic mass of isotope II (c) Zn + 2HNO 3 → Zn(NO 3 )2 + H 2 ↑ +1 −2 +2 − 1
(conc. ) (d) Na 2 SO 4 + BaCl 2 +2 −2 +1 − 1
× %age of isotope II
+ → Ba SO 4 + 2Na Cl
100 (d) 4Zn + 10HNO 3 → 4Zn(NO 3 )2
(dil. ) (No change in oxidation states)
As it is given that, the proportion of two + N 2O ↑ +5H 2O
isotopes of oxygen with masses 16 u ∴It is clear from the above equations,
Thus, in option (a) contains the reaction that in option (c), the reaction involves
and 18 u is 3 : 1 respectively. having NO (nitric oxide) gas as one of the both oxidation and reduction.
So, they have percentage composition products. Thus, it is a redox reaction.
75% and 25% respectively.
44. Which one of the following is Abrasives includes particles of calcium (iii) It is used as an oxidising agent in
not used as fertilizer? hydrogen phosphates, aluminium many chemical industries.
(a) Ammonium nitrate hydroxide, etc. Tooth pastes are basic in Hence, statement given in option (a) is
(b) Ammonium sulphide nature and prevents tooth decay by not true for bleaching powder.
(c) Ammonium phosphate neutralising the excess of acid.
They can neither be acidic nor normal. 52. Which one of the following is
(d) Ammonium sulphate
the number of water molecules
_ (b) Ammonium sulphide is not used as 48. Which one of the following that share with two formula unit
fertilizer. Fertilizer are commercially gives the highest amount of of CaSO 4 in plaster of Paris?
produced plants nutrients. It increase the hydrogen ions (H + ) ? (a) One (b) Two
fertility of soil by supplying nitrogen,
phosphorus, potassium and other (a) Sodium hydroxide solution (c) Five (d) Ten
nutrients. These are used to ensure good (b) Milk of magnesia
(c) Lemon juice (d) Gastric juice _ (a) Plaster of Paris is chemically
vegetative growth giving rise to healthy known as calcium sulphate
plants. _ (c) Acidity is a measure of the hemihydrate  CaSO 4 ⋅ H 2O  .
1
+
There are following types of fertilizers– concentration of hydrogen ions (H )  2 
Nitrogenous fertilizers, phosphatic present when a substance is dissolved in Thus, with two formula unit of CaSO 4 ,
fertilizers and NP fertilizers. a liquid. Among the given options, lemon one molecule of water is shared.
45. Which one of the following is juice is the most acidic substance.
It is prepared by heating gypsum at
the chemical formula of gypsum? Thus, it has highest amount of hydrogen 393 K.
(a) CaSO 4 .2H 2O (b) Ca 2SiO 4
ions. 2 (CaSO 4 ⋅ 2H 2O)  393
 K
→
(c) 2CaSO 4 .H 2O (d) CaSO 4 49. Brine is an aqueous solution of Gypsum 1
CaSO 4 ⋅ H 2O
2
_ (a) Gypsum has the chemical formula (a) NaCl (b) NaOH Plaster of Paris
(CaSO 4 ⋅ 2H 2O). It is a white crystalline (c) NaHCO 3 (d) Na 2CO 3
solid which is associated with two 53. How is carbon black obtained?
molecules of water of crystallisation. _ (a) Brine is an aqueous solution of (a) By heating wood at high
sodium chloride (NaCl). Electrolysis of
It is used in the production of plaster of temperature in absence of air
brine produces sodium hydroxide
Paris and in ammonium sulphate (NaOH), chlorine (Cl 2) and hydrogen (H 2). (b) By heating coal at high temperature
(NH 4 )2SO 4 fertilizer. This forms the basis of the chlor-alkali in absence of air
industries. (c) By burning hydrocarbons in a
46. Which one of the following
limited supply of air
statements about the law of 50. Which one of the following is (d) By heating coal at high temperature
conservation of mass is correct? the chemical formula of washing in presence of air
(a) A given compound always contains soda ?
exactly same proportion of elements.
(a) NaHCO 3 (b) Na 2CO 3 ⋅ 10H 2O _ (c) Carbon black is obtained by burning
(b) When gases combine in a reaction, hydrocarbons in a limited supply of air.
(c) Na 2CO 3 ⋅ 5H 2O (d) NaOH
they do so in a simple ratio by CH 4 + O 2 → C + 2H 2O
volume, provided all gases are at _ (b) Washing soda is sodium carbonate Limited Carbon
black
room temperature. or salt of carbonic acid with chemical supply
(c) Matter can neither be created nor formula of Na 2CO 3 ⋅ 10H 2O. Its anhydrous 54. Which one of the following
be destroyed. form, i.e. Na 2 CO 3 is called soda ash. properties is not true for graphite?
(d) Equal volumes of all gases at same It is a basic salt because when it (a) Hybridisation of each carbon atom
temperature and pressure contain dissolved in water, it gives a strong is sp3
equal number of molecules. base NaOH. (b) Hybridisation of each carbon atom
_ (c) Law of conservation of mass states is sp2
that, matter can neither be created nor 51. Which one of the following is (c) Electrons are delocalised over the
be destroyed. not true for bleaching powder? whole sheet of atoms
In a chemical reaction, (a) It is used as a reducing agent in (d) Each layer is composed of
Total mass of reactants = total mass of chemical industries hexagonal rings
products. (b) It is used for bleaching wood pulp
in paper factories _ (a) A graphite crystal consists of layers
of carbon atoms or sheets of carbon
(c) It is used for disinfecting drinking
atoms. Each carbon atom in a graphite
2018 (I) water
(d) It is used for bleaching linen in
layer is joined to other three carbon
atoms by strong covalent bonds to form
textile industry flat hexagonal rings. In this case, only 3
47. Which of the following properties of the 4 valence electrons of C
is true for a tooth paste? _ (a) Bleaching powder (CaOCl 2 ) is
produced by the action of chlorine on dry participate in bonding.
(a) It is acidic
slaked lime [Ca(OH)2 ]. The following are Thus, the hybridisation is sp2 having
(b) It is neutral the uses of bleaching powder: covalent bonds with other 3C-atoms in
(c) It is basic same plane.
(d) It is made up of calcium phosphate, (i) It is used for bleaching purposes in
The electrons are delocalised over the
the material of tooth enamel textile industries, paper industry and
whole sheet of atoms which makes it
in laundry. good conductor of electricity.
_ (c) Tooth pastes are derived from (ii) It is also used as a disinfectant for Thus, among the given options, option
different variety of components namely
water to make it free of germs. (a) is incorrect.
abrasives, fluoride and detergents.
55. Which one of the following is _ (a) The boiling point of water is lower at
the purest form of carbon? 2017 (II) higher altitudes due to the decreased
atmospheric pressure. This may cause
(a) Charcoal (b) Coke
an increase in cooking time.
(c) Fullerene (d) Carbon black 59. Which one of the following is a
cause of acid rains? 63. How much CO2 is produced on
_ (d) Carbon black (lamp black) is the
most purest form of carbon. It contains (a) Ozone heating of 1 kg of carbon ?
about 98-99% of carbon. It is used for (b) Ammonia 11 3 4 3
(a) kg (b) kg (c) kg (d) kg
making printer ink, black paint, varnishes (c) Sulphur dioxide 3 11 3 4
and carbon papers. (d) Carbon monoxide
_ (a) C + O 2 —→ CO 2
Charcoal is the impure form of carbon _ (c) Acid rain is caused by a variety of 12 g of C on heating produces
because of its porous structure and human activities that emit the oxides of
large surface area. sulphur and nitrogen in the atmosphere. = 44 g of CO 2
12 44
Coke contains 80-85% carbon. It is These substances can rise very high into kg of C produces = kg
the atmosphere, where they mix and 1000 1000
used as a fuel and as a reducing agent
in metallurgy. react with water, oxygen and other of CO 2
Fullerene is an allotrope of carbon
chemicals to form more acidic pollutants, ∴ 1 kg of C produces
known as acid rain. 44 1000
whose molecules consists of carbon = × kg of CO 2
atoms connected by single and double 1000 12
60. The desirable range of pH for 11
bonds. drinking water is = kg
3
56. The poisonous nature of carbon (a) 6 . 5 to 8 . 5 (b) 5 . 0 to 6 . 5
monoxide (CO) is due to its (c) 6 . 5 to 7 .0 (d) 7 . 0 to 8 . 5 64. Zinc is used to protect iron from
corrosion because zinc is
(a) insolubility in water _ (c) The pH of pure water is 7. In general,
(b) ability to form a complex with water with a pH lower than 7 is (a) more electropositive than iron
haemoglobin considered acidic and with a pH greater (b) cheaper than iron
(c) ability to reduce some metal oxides than 7 is considered basic. The normal (c) a bluish white metal
(d) property of having one σ-bond range for pH in surface water systems is (d) a good conductor of heat and
6.5 to 8.5 and the pH range for electricity
_ (b) Carbon monoxide (CO) is highly groundwater systems is between
poisonous to living beings because it has
6 to 8.5. _ (a) Zinc metal is used to protect iron
an ability to form more stable from corrosion because zinc is more
carboxyhaemoglobin. It is 300 times more 61. Consider the following reaction, electropositive than iron.
stable than oxygen-haemoglobin complex. The process of coating iron land steel
CH4 + 2O2 → CO2 + 2H2 O.
In blood, when the concentration of objects with a thin layer of zinc is called
carboxyhaemoglobin reaches about 3-4 Which of the following about galvanisation.
percent. The oxygen carrying capacity Zinc metal present on the surface of iron
of blood is greatly reduced. The oxygen
the reaction given above is/are
forms a thin protective layer of basic
deficiency results headache, weak correct? zinc carbonate due to the reaction
eyesight, nervousness, etc. 1. Carbon is oxidised between zinc, oxygen, CO 2 and
2. Hydrogen is oxidised moisture in air.
57. Which one of the following alkali
3. Hydrogen is reduced Since, zinc is more electropositive than
metals has lowest melting point?
4. Carbon is reduced iron.
(a) Sodium (b) Potassium
(c) Rubidium (d) Caesium Select the correct answer using 65. Which one of the following
the code given below : gases is placed second in respect
_ (d) The melting point of alkali metals (a) Only 1 (b) 1 and 2
decreases on moving down the group of abundance in the Earth’s
(c) 2 and 3 (d) 2 and 4 atmosphere?
due to decrease in the extent of metallic
bonding. Thus, the sequence of melting _ (a) According to the following reaction, (a) Oxygen (b) Hydrogen
point among the given options is CH 4 + 2O 2 → CO 2 + 2H 2O (c) Nitrogen (d) Carbon dioxide
Na > K > Rb > Cs it is a combustion reaction of methane.
_ (a) The permanent gases whose
Therefore, caesium (Cs) has the least In this kind of reaction, carbon dioxide percentages do not change from day to
melting point. and water are always the products. day are nitrogen, oxygen and argon.
Here, methane gets oxidised and Nitrogen accounts for 78% of the
58. Which one of the following
oxygen gas gets reduced. atmosphere, oxygen 21% and argon
metals is alloyed with sodium to
Hence, the reaction is 0.9%: Gases like carbon dioxide, nitrous
transfer heat in a nuclear reactor? oxidation-reduction type of reaction in oxides, methane and ozone are trace
(a) Potassium (b) Calcium which methane is reducing agent and gases that account for about a tenth of
(c) Magnesium (d) Strontium oxygen gas get reduced. one percent of the atmosphere.
_ (a) Sodium-potassium alloy (NaK) is an 62. Water boils at a lower temperature 66. Which one of the following is a
alloy of two alkali metals-sodium and at high altitudes, because chemical change?
potassium. It is used as a heat-transfer. (a) the air pressure is less (a) Cutting of hair
Coolant in fast-breeder nuclear reactors (b) outside temperature is less (b) Graying of hair naturally
and experimentally in gas-turbine power (c) latent heat is less (c) Swelling of resin in water
plants. (d) None of the above (d) Cutting of fruit
 40
_ (b) A chemical change (chemical Ar + → Number of electrons
reaction) is a change of materials into 18 2017 (I)
other, new materials with different = 18 − 1 = 17
properties, and one or more new 35 2−
S → Number of electrons 75. Molecules of which of the
substances are formed. 16 following has cage like
These process are, in general are not = 16 + 2 = 18
reversible except by further chemical 35 40 +
structure?
reaction. Hence, graying of hair is the ∴ Cl and Ar has the same 1. Diamond 2. Graphite
17 18
correct answer as that cannot be 3. Fullerenes
number of electrons.
reversed. Select the correct answer using
67. Which one among the following 71. The compound C6 H12 O4 the code given below.
chemicals is used as washing contains (a) All of these (b) 2 and 3
(a) 22 atoms per mole (c) Only 2 (d) Only 3
soda?
(b) twice the mass percent of H as
(a) Calcium carbonate
compared to the mass percent of C
_ (d) Fullerenes C 60 has cage like
(b) Calcium bicarbonate structure. It is made by heating graphite
(c) six times the mass percent of C as in an electric arc in the presence of inert
(c) Sodium carbonate compared to the mass percent of H
(d) Sodium bicarbonate gases such as helium or argon.
(d) thrice the mass percent of H as It is the only pure form of carbon.
_ (c) Sodium carbonate (Na 2CO 3) is used compared to the mass percent of O
as washing and cleansing purpose in
76. Temporary hardness in water is
_ (c) Molar mass of C in C 6H12O 4 due to which one of the following
houses. That’s why, it is called as
= 6 × 12 = 72 of calcium and magnesium?
washing soda.
Molar mass of H in C 6H12O 4 (a) Hydrogen carbonates
68. Why is potassium permanganate = 1 × 12 = 12 (b) Carbonates
used for purifying drinking water? ∴Mass percent of C is six times as (c) Chlorides
(a) It kills germs compared to the mass percent of H. (d) Sulphates
(b) It dissolves the impurities
72. The ionisation energy of _ (b) Temporary hardness or carbonate
(c) It is a reducting agent hardness is due to the presence of
(d) It is an oxidising agent hydrogen atom in the ground
soluble calcium hydrogen carbonate
state is Ca(HCO 3 )2 and magnesium hydrogen
_ (d) Potassium permanganate (KMnO 4 ) is (a) 13 . 6 MeV (b) 13 . 6 eV carbonate Mg(HCO 3 )2.
a strong oxidising agent and is used for (c) 13 . 6 Joule (d) Zero
purifying water and treat stinking wells. It can be removed by boiling and Clark’s
_ (b) For a hydrogen atom, composed of method.
69. The principal use of hydrofluoric an orbiting electron bound to a nucleus of
77. Which one of the following
acid is one proton, an ionisation energy of
2.18 × 10 –18J (13.6 eV) is required to force elements is least reactive with
(a) in etching glass
(b) as a bleaching agent the electron from its lowest energy level water?
(c) as an extremely strong oxidising agent entirely out of the atom. (a) Lithium (b) Sodium
(d) in the preparation of strong organic (c) Potassium (d) Cesium
73. When pure water boils
fluorine compounds vigorously, the bubbles that rise _ (a) Among given elements, lithium is
least reactive with water. Lithium density
_ (a) The principal use of hydrofluoric acid to the surface are composed is only about half of water.
[HF] is in etching glass. This technique is primarily of
used for creating art on the glass (a) air 78. Rutherford’s alpha-particle
surfaces. scattering experiment was
(b) hydrogen
70. The species that has the same (c) hydrogen and oxygen responsible for the discovery of
number of electrons as, 35
17
Cl is (d) water vapour (a) electron (b) proton
(c) nucleus (d) helium
32 34 40 35 2− _ (d) When pure water boils vigorously, the
(a) S (b) S + (c) Ar + (d) S
16 16 18 16 bubble that rise to the surface are _ (c) Rutherford’s alpha-particle scattering
composed primarily of water vapour. experiment was responsible for the
_ (c) Number of electrons = Number of 74. Which compound, when
discovery of atomic nucleus.
protons = Atomic number. He proposed that, there is a positively
Mass number
dissolved in water, conducts charged spherical centre in an atom,
A electricity and forms a basic
X Symbol called the nucleus. Nearly, all the mass of
Z
solution? an atom resides in the nucleus.
Atomic number (a) HCl
79. Glass is a
35 (b) CH 3COOH
Cl → Number of electrons = 17. (a) liquid (b) colloid
17 (c) CH 3OH (c) non-crystalline amorphous solid
32 (d) NaOH (d) crystalline solid
S → Number of electrons = 16.
16 _ (d) NaOH, when dissolved in water, _ (c) Glass is a homogeneous mixture of
34 + conducts electricity and forms a basic silicates of various alkaline metals of
S → Number of electrons solution. Strong electrolyte conducts non-crystalline amorphous solid. The
16
electricity in solution. ordinary glass has approximately the
= 16 − 1 = 15 composition of Na 2 O ⋅ CaO ⋅ 6SiO 2.
80. Which one of the following _ (a) Among the given elements, iron ● Neon is used in fluorescent bulbs for
statements is not correct? corrodes rapidly. The corrosion of advertisement display purposes.
aluminium starts rapidly first but a ● Krypton is used as airport landing
(a) In the conduction mode of
passive layer is formed after sometime lights and in light houses.
transference of heat, the molecules due to which rate of corrosion decreases.
of solid pass heat from one Hence, the rate of corrosion is highest in ● Xenon is used in high intensity
molecule to another without moving iron. photographic flash tubes.
from their positions.
(b) The amount of heat required to raise 85. 20 g of common salt is dissolved 88. Why is it difficult to measure
the temperature of a substance is in 180 g of water. What is the the coefficient of expansion of a
called its specific heat capacity. mass percentage of the salt in liquid than solid?
(c) The process of heat transfer in the solution? (a) Liquids tend to evaporate at all
liquids and gases is through (a) 5% (b) 9% (c) 10% (d) 15% temperatures
convection mode. (b) Liquids conduct more heat
(d) The process of heat transfer from a _ (c) Mass of solute (salt) = 20 g (c) Liquids expand too much when heated
body at higher temperature to a Mass of solvent (water) = 180 g (d) Their containers also expand when
We know that,
body at lower temperature without heated
Mass of solution =
heating the space between them is
Mass of solute + Mass of solvent _ (d) Liquids can be heated only by putting
known as radiation. = 20 g + 180 g = 200 g them in a container. So, when heat is
_ (b) The amount of heat required to raise Mass percentage of salt in the solution provided to the liquid, the container also
the temperature of a substance is called its Mass of solute expands.
specific heat capacity is not correct, = × 100
because specific heat capacity represents
Mass of solution 89. Radon is
20 (a) an inert gas
the amount of heat required to raise the = × 100 = 10%
temperature of 1 kg of a body by 1° C. 200 (b) an artificial fibre
Hence, statement given in option (b) is not (c) an explosive
correct.
86. The valency of an element (d) a metal
depends upon the
81. The amount of heat required to (a) total number of protons in an atom _ (a) Radon is an inert gas. It is placed in
change a liquid to gaseous state group 18 of the periodic table. It is called
(b) mass number of an atom
inert gas because of it is chemically inert
without any change in (c) total number of neutrons in an atom
in nature.
temperature is known as (d) total number of electrons in the
(a) specific heat capacity outermost shell of an atom 90. Which one of the following
(b) mechanical equivalent of heat
_ (d) Valency is the combining capacity of elements is used in pencil-lead?
(c) latent heat of vaporisation an atom. It depends upon the total (a) Zinc (b) Lead
(d) quenching number of electrons in the outermost (c) Carbon (Graphite) (d) Tin
shell of an atom. An outermost shell
_ (c) The amount of heat required to which has eight electrons is said to _ (c) The allotrope of carbon, i.e. graphite
change a liquid to gaseous state without is used for marking on the paper in the
posses an octet.
any change in temperature is known as form of lead pencil. It is also known as
latent heat of vaporisation. 87. Match List I with List II and the black lead.
select the correct answer using
82. A homogeneous mixture
contains two liquids. How are
the code given below the Lists. 2016 (II)
they separated? List I (Noble gas) List II (Use)
(a) By filtration (b) By evaporation A. Argon 1. In lights for 91. Match List I with List II and
(c) By distillation (d) By condensation advertising display select the correct answer using
B. Neon 2. Airport landing the codes given below the Lists.
_ (c) Homogeneous mixture containing
two liquids can be separated by lights and in light
List I List II
distillation method. It is based on the houses
(Process) (Type of change)
difference in the boiling points of the C. Krypton 3. Light in
liquids in the given mixture. photographer’s A. Heating camphor 1. Chemical
flash gun B. Cooling of water 2. Evaporation
83. Which one of the following
D. Xenon 4. In tungsten filament vapour upto room
elements forms highest number temperature
to last longer
of compounds?
C. Cooking an egg 3. Condensation
(a) Oxygen (b) Hydrogen Codes
(c) Chlorine (d) Carbon A B C D D. Formation of water 4. Sublimation
(a) 3 1 2 4 vapour at room
_ (d) Among the given elements, carbon has (b) 3 2 1 4 temperature
maximum number of compounds. The (c) 4 2 1 3
estimated number of carbon compounds Codes
(d) 4 1 2 3
known today is about three millions. A B C D
84. Which one of the following _ (d) The correct matching is A-4, B-1, C-2, (a) 4 3 1 2
D-3. (b) 4 1 3 2
elements corrodes rapidly? Argon is used for filling in tungsten
●
(c) 2 1 3 4
(a) Aluminium (b) Iron filament to last longer. (d) 2 3 1 4
(c) Zinc (d) Silver
 _ (a) The correct matching is A-4, B-3, 48 g oxygen = 3 × 6.022 × 10 23 atoms explosions. To avoid this, ethyl
C-1, D-2. 3 mercaptan (CH 3CH 2SH) or ethanethiol
= × 6.022 × 10 23 molecules
● Cooking an egg is a chemical 2 (CH 3 CH 2 SH) is added to the gas,
change because a substance with (As oxygen is diatomic molecule.) which possesses that strong odour of
new chemical composition is 12 g carbon = 6.022 × 10 23 atoms cabbages. The smell helps us to detect,
formed, which is not converted into 1 when there is a leak, which actually
2 g carbon = × 6.022 × 10 23 atoms makes a lot of sense from a safety and
its initial state by process. 6
● Evaporation is the process of 1 security perspective.
= × 6.022 × 10 23 molecules
conversion of substance from liquid 6 98. A plant having yellow leaves with
state to vapour state at any (As carbon is monoatomic molecules.) dead spots has the deficiency of
temperature below its boiling point is Hence, 2 g of carbon contains different
called evaporation. (a) potassium
number of molecules.
(b) magnesium
● Condensation is the process of
change of state of a substance from
95. Which one of the following (c) nitrate
statements is correct? (d) phosphate
its gaseous state to liquid state at a
particular temperature, is called (a) Covalent bonds are directional _ (a) A plant having yellow leaves with
condensation. (b) Ionic bonds are directional dead spots, has the deficiency of
(c) Both covalent and ionic bonds are potassium.
● Sublimation is the process of
conversion of a substance from solid directional Magnesium is the part of chlorophyll in
state to vapour state without going (d) Both covalent and ionic bonds are all green plants, so lack of Mg 2 +
through liquid state is called non-directional causes chlorosis and tissue damaged,
sublimation. Heating camphor while lack of phosphate causes leaves
_ (a) Covalent bond is formed by sharing dull and causes curled disease.
follows sublimation. of electrons between atoms by
overlapping of the atomic orbitals of Lack of nitrate causes green or white
92. Identify the element having zero participant atoms and usually only few purple and red spots of anthocyanin,
valency. patterns of overlap are possible. chlorosis with necrosis, first in older
(a) Sulphur (b) Phosphorus Consequently, only few spatial leaves or premature abscission, delayed
(c) Lead (d) Radon arrangement of atom are possible. flowering and fruiting.
_ (d) Valency of inert gases is zero These limitations determine the direction 99. Fluoride toothpaste is sometimes
because they have completely filled of bonds.
recommended, because fluoride
valence shell and do not combine with
other elements to form compounds, i.e. 96. When one strikes a safety (a) prevents plaque formation
their octet is completely filled. match, the first step is (b) hardens the enamel of the tooth
(a) burning of sulphur (c) kills pathogenic bacteria
Radon is an example of zero valency
(b) decomposition of potassium (d) prevents toothache
among given options.
chlorate into potassium chloride _ (a) Fluoride toothpaste is sometimes
93. There are six electrons, six and oxygen recommended because fluoride prevents
protons and six neutrons in an (c) conversion of a small amount of plaque formation and it promotes new
atom of an element. What is the red phosphorus into white bone formation. It is used for
atomic number of the element? phosphorus strengthening of bone. Fluoride is added
(a) 6 (b) 12 (c) 18 (d) 24 (d) burning of glue and starch to public drinking water to prevent tooth
decay.
_ (a) The number of protons or electrons _ (c) Head of matchstick of safety match is
of an atom is called atomic number. made up of antimony trisulphide and 100.Combination of one volume of
Here, number of protons and number of potassium chlorate, while frictionable nitrogen with three volumes of
electrons are six each. surface is made of red phosphorus. hydrogen produces
Hence, atomic number of element is 6. When matchstick is rubbed against the (a) one volume of ammonia
striking surfaces, the friction generates (b) two volumes of ammonia
94. Which one of the following has enough heat to convert a trace of the red (c) three volumes of ammonia
different number of molecules? phosphorus into white phosphorus. (d) one and a half volumes of ammonia
(All are kept at normal
temperature and pressure) 97. The LPG cooking gas contains _ (b) The law of combining volume (for
propane and butane as the gases) states that, when gases react
(a) 3 g of hydrogen (b) 48 g of oxygen with each other, they follow,
(c) 42 g of nitrogen (d) 2 g of carbon constituents. A sulphur
Gay-Lussac’s law.
containing compound is added
_ (d) The mass of 1 mole of a substance is to the LPG, because The volume of reactants and products in
equal to its relative atomic or molecular a large number of chemical reactions
mass in grams. (a) it lowers the cost of production are related to each other by small
(b) it enhances the efficiency of LPG integers, provided the volumes are
1 mole = 6.022 × 10 23
(c) it facilitates easy detection of measured at the same temperature and
1g hydrogen = 6.022 × 10 23 atoms leakage of the gas pressure.
3g hydrogen = 3 × 6.022 × 10 23 atoms (d) it assists in liquefying hydrocarbons As per balance equation,
3
= × 6.022 × 10 23 molecules _ (c) LPG gas is basically propane and N2 + 3H2 Fe /Mo

→
2
butane, and it is odourless in its natural (1 volume) (3 volume) (450-500°C)
(200 atm)
(Since, hydrogen is diatomic molecule.) state. LPG is very dangerous, because if 2NH3 + Heat
16 g oxygen = 6.022 × 10 23 atoms it leaks, it can cause terrible fires and (2 volume)
 −
101.The setting time of cement is _ (d) CIO 4 is the perchlorate ion, where 110.Which one of the following
lowered by adding chlorine avails at its maximum oxidation elements will not react with
(a) oxides of aluminium stage i.e. +7, therefore it cannot be dilute HCl to produce H2 ?
(b) gypsum reoxidise. Disproportionation is a specific (a) Hg (b) Al (c) Mg (d) Fe
(c) oxides of magnesium type of redox reaction in which an element
(d) silica from a reaction undergoes both oxidation _ (a) Hg will not react with dilute HCl to
and reduction to form different products. produce H 2 because in reactivity series,
_ (b) Gypsum is often added to Portland Hg is less reactive than the given, i.e. the
cement to prevent early hardening or
‘‘flash setting, allowing a longer working 2016 (I) hydrogen which has a stronger attraction
to the Cl than the mercury.
time.” It shows down the setting of
cement, so that cement is adequately 107.Which one of the following 111.When a solid is heated, it turns
hardened. oxides dissolve in water ? directly into a gas. This process
102.Emulsion is known as a (a) CuO (b) Al 2O 3 (c) Fe 2O 3 (d) Na 2O is called
(a) condensation (b) evaporation
(a) colloidal solution of substances _ (d) Sodium oxide (Na 2O) is the base (c) sublimation (d) diffusion
having different physical states anhydride of sodium hydroxide, when
(b) true solution water is added to it, NaOH is produced. _ (c) Sublimation is the change of state
(c) distillation mixture for making Na 2O + H 2O → 2NaOH from solid state directly to gaseous state
alcohols without going through liquid state and
It is used in ceramics and glasses, vice-versa.
(d) colloidal solution of two liquids though not in a raw form and rest of all
_ (d) Liquid-liquid colloidal systems in are not dissolved in water. 112.Which one of the following is
which finely divided droplets of a liquid CuO, Al 2O 3,Fe 2O 3 are water insoluble. water gas?
are dispersed into other liquid, are called (a) Mixture of carbon monoxide and
emulsions. These are formed by shaking 108.Matter around us can exist in
three different states namely, hydrogen
the two immiscible liquids with each other. (b) Mixture of carbon monoxide and
solid, liquid and gas.
103.If one mixes up ashes with nitrogen
Correct order of their
animal fat, the substance received (c) Mixture of carbon dioxide and water
compressibility is
vapour
in the crude form is called (a) liquid < gas < solid
(d) Mixture of carbon monoxide and
(a) pheromone (b) soap (b) solid < liquid < gas
water vapour
(c) cement (d) concrete (c) gas < liquid < solid
+ + 2+ (d) solid < gas < liquid _ (a) Water gas is a mixture of carbon
_ (b) Metal salts (e.g. Na , K , Ca ) are monoxide (CO) and hydrogen (H 2 ) in
one of the constituents of ash. When _ (b) The correct order of compressibility is which nitrogen and water vapour is in the
ashes are mixed up with animal fat, the solid < liquid < gas.
form of impurity. The gas is made by
salt of fatty acid is obtained, which is Gases are highly compressible as
passing steam over a red hot carbon fuel
called soap. compared to solids and liquids. In gas, the
such as coke.
molecules have enough kinetic energy so
104.Which one of the following that the effect of intermolecular forces is
gases give acidic solution on small and the typical distance between 113.A glass vessel is filled with water
dissolving in water ? neighbouring molecules is much greater up to the brin and a lid is fixed
(a) Hydrogen (b) Carbon dioxide than the molecular size.
to it tightly. Then it is kept
(c) Nitrogen (d) Oxygen 109.The temperature at which a inside a freezer for hours.
_ (b) Carbonic acid is a weak acid that solid melts to become a liquid at What is expected to happen?
causes a slight drop in pH (makes the the atmospheric pressure is (a) The water freezes to ice and the
solution more acidic). When CO2 called its melting point. The level of ice comes down
dissolves in water, it forms carbonic acid melting point of a solid is an (b) The water in the glass vessel
(H2CO3). This compound has a higher K a indication of summer freezes to ice
value ~ 10 −3 than water. This means that, (c) The glass vessel breaks due to
(a) strength of the intermolecular forces
the H2CO3 is more likely to dissociate and expansion as water freezes to ice
of attraction
produce H + ions in solution. (d) The water does not freeze at all
(b) strength of the intermolecular forces
105.How many moles of hydrogen of repulsion
_ (a) Water shows anomalous behaviour in
atom are present in one mole of (c) molecular mass the expansion during temperature range
aluminium hydroxide? (d) molecular size of 4°C to 0°C. When the temperature falls
(a) One mole (b) Two moles _ (a) The melting point of a solid is an below 4°C, water expands. As lid is fixed
(c) Three moles (d) Four moles indication of strength of intermolecular tightly, the stress will develop in the bottle
force of attraction. On increasing the due to this anomalous expansion which
_ (c) As molar formula of aluminium temperature of solids, the kinetic energy breaks the glass when water is converted
hydroxide is Al(OH)3. Therefore, each into ice i.e., volume is maximum.
mole of Al(OH) 3 contains three moles of of the particles increases. Due to the
hydrogen atom. increase in kinetic energy, the particles 114.Suppose you have four test
start vibrating with greater speed. tubes labelled A, B, C and D.
106.Which one of the following The energy supplied by the heat
species is not capable of showing A contains water, B contains
overcomes the forces of attraction
disproportionation reaction? between the particles. A stage is
solution of an alkali, C contains
(a) CIO − (b) CIO −2 (c) CIO −3 (d) CIO −4 reached when solid melts and is solution of an acid, and D
converted into a liquid. contains solution of sodium
 chloride. Which one of these (a) Sodium bicarbonate (sodium 121.The phosphorus used in the
solutions will turn hydrogen carbonate) manufacture of safety matches is
phenolphthalein solution pink ? (b) Sodium carbonate (a) red phosphorus
(c) Potassium bicarbonate (potassium (b) black phosphorus
(a) Solution A (b) Solution B
hydrogen carbonate)
(c) Solution C (d) Solution D (c) white phosphorus
(d) Potassium carbonate
(d) scarlet phosphorus
_ (b) Solution B, i.e. solution of an alkali
will turn phenolphthalein solution pink _ (a) The chemical name of baking soda is _ (a) Red phosphorus is used in the
sodium bicarbonate (sodium hydrogen
because phenolphthalein is a weak manufacture of safety matches. Red
carbonate, (NaHCO 3). It is produced using
organic acid. It turns colourless in phosphorus exists as an amorphous
sodium chloride as one of the raw
acidic solution and pink in basic network. Red phosphorus does not ignite
materials.
solution. It is a synthetic indicator used in air at temperature below 240°C.
in acid-base titrations. NaCl + H 2O + CO 2 + NH 3 →
NaHCO 3 + NH 4Cl 122.Which one of the following is
115.An atom of carbon has 6 (Sodium hydrogen (Ammonium not a chemical change?
carbonate) chloride)
protons. Its mass number is 12. Baking soda (a) Ripening of fruits
How many neutrons are (b) Curdling of milk
present in an atom of carbon? Directions (Q. No. 119) The following (c) Freezing of water
(a) 12 (b) 6 question consist of two statements, (d) Digestion of food
(c) 10 (d) 14 Statement I and Statement II. You
have to examine these two statements _ (c) Freezing of water is a physical
change, i.e. not a chemical change
_ (b) We know that, carefully and select the answers to the because it is the interconversion of
Mass number ( A ) = number of proton question using the codes given below. states, the physical property changes but
( p) + number of neutron ( n)
Codes the chemical composition remains the
12 = 6 + n
(a) Both the statements are individually same.
⇒ Hence, number of neutrons present Remaining all are examples of chemical
true and Statement II is the correct
in atom of carbon is n = 6 change.
explanation of Statement I
116.Which one of the following is a (b) Both the statements are individually 123.Soap is the sodium or potassium
reduction reaction? true, but Statement II is not the
salt of
correct explanation of Statement I
(a) 2Mg( s ) + O 2( g ) → 2MgO( s ) (a) stearic acid
(c) Statement I is true, but Statement II is
(b) oleic acid
(b) S( s ) + O 2( g ) → SO 2( g ) false
(d) Statement I is false, but Statement II (c) palmitic acid
(c) 2HgO( s ) Heat
→ 2Hg( l ) + O 2( g ) is true (d) All of the above
(d) Mg( s ) + S ( s ) → MgS ( s ) _ (d) The mineral salts of higher fatty acids
119.Statements such as oleic acid (C 17 H 33 COOH),
Heat
I. Petroleum is a mixture of many stearic acid (C 17 H 35 COOH) and palmitic
_ (c) 2HgO( s )  → 2Hg( l ) + O 2( g ) different hydrocarbons of acid (C 15H 31COOH) etc. are called soaps.
Above reaction is a reduction reaction. different densities. Out of these, only sodium and potassium
In this reaction, HgO decomposes on salts of fatty acids being water soluble,
II. The grade of petroleum depends are widely used for cleaning purposes.
exposure to light or on heating above
500°C. Heating produces highly toxic mainly on the relative
proportion of the different 124.Which of the following carbon
mercury fumes and oxygen.
hydrocarbons. compounds will not give a sooty
117.Which one of the following flame?
oxides of nitrogen is known as _ (b) Petroleum is a mixture of a very large (a) Benzene
number of different hydrocarbons; the
‘anhydride’ of nitric acid? most common are alkanes, cycloalkanes,
(b) Hexane
(a) N 2O (b) N 2O 3 aromatic hydrocarbons etc. The relative (c) Naphthalene
(c) NO 2 (d) N 2O 5 percentage of hydrocarbons varies and is (d) Anthracene
responsible for different grades of _ (b) Hexane (C 6H14 ) will not give a sooty
_ (d) The anhydride of HNO 3 is N 2O 5,
petroleum. flame. Hexane is a significant constituent
nitrogen pentaoxide and N 2O 3 is the
anhydride of HNO 2, nitrous acid. 120.Density of water is of gasoline. The darker or sootier the
The anhydride of nitric acid is the smoke, the more unsaturated the
(a) maximum at 0°C compound. On the other hand, if the
acidic oxide which on hydration forms (b) minimum at 0°C
the acid. N 2O 5 dissolves in water to flame is burning relatively clearer and
(c) maximum at 4°C clearer then the compound is saturated.
give nitric acid. (d) minimum at − 4°C Hexane burns with a clear and luminous
N 2O 5 + H 2O → 2HNO 3
flame.
Conversely, HNO 3 on dehydration with _ (c) Water shows anomalous behaviour
between temperatures 0°C and 4°C
P2O 5 yields its anhydride, N 2O 5, 125.What is the number of mole(s)
expands it temperature goes below 4°C.
2HNO 3 + P2O 5 → N 2O 5 + 2HPO 3 of H 2( g) required to saturate one
Therefore, density decreases below 4°C.
Also, it expands when temperature goes
mole of benzene ?
118.Which one of the following is (a) 1 (b) 2
above 4°C. Therefore, density of water is
the chemical name for baking maximum at 4°C because volume is (c) 3 (d) 4
soda? minimum at 4°C.
 _ (c) 3H 2
129.Consider the following reaction, _ (b) The law of definite or constant
1270 K proportion was given by Joseph Proust.
CH4 (g) + H2 O( g)   → It states that, irrespective of source, a
Benzene Cyclohexane CO(g) + 3H2 (g) given compound always contains exactly
(Unsatureted (Saturated
compound) In the reaction given above, the the same elements in the same
compound)
proportion by weight.
3 moles of H 2( g ) is required to saturate mixture of CO and H2 is Hence, it follows law of constant
one mole of benzene. (a) natural gas (b) water gas proportion, not multiple and reciprocal
(c) producer gas (d) industrial gas proportion laws.
_ (b) According to question, 133.Boric acid is an acid because its
2015 (II) CH 4 ( g ) + H 2O( g ) → CO( g ) + 3H 2( g )
molecule
The mixture of CO and H 2 is called water
gas. This mixture of CO and H 2 is used (a) accepts OH − from water releasing
126.The symbol of the element proton
‘tungsten’ is for the synthesis of methanol and a
number of hydrocarbons. (b) combines with proton from water
(a) Ta (b) W molecule
Natural gas is a naturally occurring
(c) Tl (d) Tc (c) contains replaceable H + ion
hydrocarbon gas mixture consists of
(d) gives up a proton
_ (b) W is the symbol for element ‘tungsten’. methane and varying amount of higher
Ta is the symbol for element ‘tantalum’. alkenes. _ (a) Boric acid is a weak monobasic acid.
Tl is the symbol for element ‘thallium’. Producer gas, also called suction gas, It is not a protonic acid, but acts as a Lewis
Tc is the symbol for element is a fuel gas made from coke, anthracite acid by abstracting OH − from water.
‘technetium’. or other carbonaceous fuel. B(OH )3 + 2H 2 O s B(OH )4− + H 3O +
127.Which one of the following Industrial gases are a group of gases
that are specifically manufactured for 134.The main constituent of vinegar
statements is correct? use in industries. is
(a) Rutherford’s α-particle scattering (a) acetic acid
experiment led to the discovery of 130.Addition of gypsum to cement (b) ascorbic acid
electron (a) reduces setting time of cement (c) citric acid
(b) J.J. Thomson suggested that the (b) produces very light colour of cement (d) tartaric acid
nucleus of an atom contains (c) increases setting time of cement
protons (d) shining surface is formed _ (a) The main constituent of vinegar is
(c) The atomic number of an acetic acid (CH 3COOH). Commercially, it
element is the same as the _ (c) Gypsum is a mineral and is hydrated is produced by fast or slow fermentation
calcium sulphate in chemical form. It process which involves yeast (fungus).
number of protons in the plays an important role in controlling the
nucleus of its atom Citric acid is present in lemons or
rate of hardening of cement. It is added
(d) The mass number of an atom is to control the ‘setting of cement’. If not oranges. Tartaric acid is present in
equal to the number of electrons in added, the cement will set immediately tamarind. Ascorbic acid is present in all
its shells after mixing of water leaving no time for citrus fruits.
concrete placing.
_ (c) Atomic number of an element is 135.White phosphorus glows in the
equal to the number of protons in the 131.To weld metals together, high dark due to
nucleus of its atom. Hence, it is the temperature is required. Such a (a) amorphous character
correct statement. high temperature is obtained by (b) slow oxidation
In other options, (c) high ignition temperature
burning.
In 1911, Ernest Rutherford’s α-scattering (d) good conducting property of electricity
(a) acetylene in oxygen
experiment led to the discovery of
(b) LPG in oxygen _ (b) The slow oxidation is actually a
nucleus in an atom.
J.J. Thomson’s cathode ray tube (c) methane in oxygen reaction of white phosphorus with
experiment led to the discovery of (d) acetylene in nitrogen oxygen (at some partial pressure)
forming short lined molecules such as
electrons. _ (a) To weld metals together, high HPO and P2O 2 that on stabilising emits
Mass number of an atom is equal to the temperature is obtained by burning
acetylene in oxygen. visible light.
sum of total number of neutrons and
White phosphorus + Oxygen →
protons in the nucleus. Pure oxygen is used to increase the (P4 ) (O 2)
flame temperature to allow localised
128.The alkali metals have relatively melting of the work piece material. [Short -lined intermediates]
low melting point. Which one of An acetylene/oxygen flame burns at → [Final product]
the following alkali metals is about 3,773 K. (HPO, P2O 2, etc.)
expected to have the highest Light-energy (Glow)
132.Ammonia (NH3 ) obtained from
melting point? 136.Which of the following are the
different sources always has
(a) Li (b) Na
same proportion of nitrogen and properties of an electron?
(c) K (d) Rb
hydrogen. It proves the validity 1. Electron is a constituent of
_ (a) On moving from Li to Cs, size of atom the law of cathode ray.
increases, so interatomic interaction
(a) reciprocal proportion 2. Electron is a negatively charged
becomes weak resulting in low melting
(b) constant proportion particle.
point. Among alkali metals, Li has the
highest melting point. (c) multiple proportions
(d) None of the above
 3. The mass of the electron is Codes Codes
equal to the mass of the proton. A B C D (a) Both the Statements are individually
(a) 2 3 4 1 true and Statement II is the correct
4. Electron is deflected by the (b) 1 2 3 4
electric field but not by explanation of Statement I
(c) 2 4 3 1
magnetic field. (d) 1 3 2 4 (b) Both the Statements are individually
true but Statement II is not the
Select the correct answer using the _ (a) The correct matching is A-2, B-3, C-4, correct explanation of Statement I
codes given below. D-1.
(a) 1 and 2 (b) 1, 2 and 3 (c) Statement I is true, but Statement II
● Lithium (Li) is used in batteries and
(c) 3 and 4 (d) 1 and 4 is false
is widely known as lithium batteries.
These are disposable and (d) Statement I is false, but Statement II
_ (a) J.J. Thomson discovered electron in is true
cathode ray tube experiment so, it is can produce 1.5-3.7 V.
considered as the constituent of cathode ● Sodium (Na) is used in transfer of 140.Statement I The granules of
ray. nerve impulse. Sodium ions move
modern gunpowder (also called
It is a negatively charged particle and is inside the membrane when a
stimulus reaches a resting neuron black powder) are typically
deflected by both electric and magnetic
field. and at complete depolarisation, coated with graphite.
action potential is created. Statement II Graphite
137.Which of the following ● Potassium (K) is available in fruits prevents the build-up of
statements regarding heavy and vegetables; and sodium (Na) is electrostatic charge.
water are correct? available in salts. Eating salt raises
1. It is extensively used as a amount of sodium which reduces the _ (b) The granules of modern gunpowder
ability of kidney to remove water, (black powder) are coated with graphite
moderator in nuclear reactors. as graphite dramatically reduced the
whereas potassium helps kidney to
2. It cannot be used in exchange work efficiently in retaining water. moisture absorbing capacity of the
reaction to study reaction powder. Graphite prevents the build-up
● Caesium (Cs) atomic clocks are the of electrostatic charge. So, option (b) is
mechanism. most accurate time keepers. These the correct answer.
3. Viscosity of heavy water is are the devices that contain a
relatively smaller than that of ‘pendulum’ of atoms that are excited 141.Statement I Colour of nitrogen
ordinary water. into resonance by microwave dioxide changes to colourless at
radiation. Definition of ‘SI’ unit of time low temperature.
4. The dielectric constant of is based on these clocks.
heavy water is smaller than that So, option (a) is the correct answer.
Statement II At low
of ordinary water. temperature, nitrogen tetraoxide
Select the correct answer using the 139.Graphite is a much better (N2O 4 ) is formed, which is
conductor of heat and electricity colourless.
codes given below.
(a) 1 and 2 (b) 2 and 3 than diamond. This is due to
the fact that each carbon atom _ (a) It is obvious from above statements
(c) 3 and 4 (d) 1 and 4 that with fall in temperature, nitrogen
in graphite dioxide (NO 2) molecules associate to
_ (d) Heavy water is used as a moderator 2
(a) undergoes sp hybridisation and give formation of colourless nitrogen
in nuclear reactors and its dielectric
forms three sigma bonds with three tetraoxide (N 2 O 4 ).
constant is smaller than the ordinary
water. neighbouring carbon atoms 2NO 2
e N2O 4
[Deuterium is heavier than hydrogen] (b) undergoes sp3 hybridisation
NO 2 is favoured at higher temperatures,
(c) is tetrahedrally bonded while at lower temperatures, N 2 O 4
It is extensively used in exchange
(d) is free from van der Waals’ force predominates. So, option (a) is the
reactions for the study of reaction
mechanism. _ (a) Graphite is a good conductor of heat correct answer.
Its density is higher than water. and electricity because of the presence of
one free electron on each carbon atom as
142.Statement I Oxygen gas is
Hence, its viscosity is also higher than
ordinary water. each carbon have sp2 hybridisation easily produced at a faster rate
(forms three sigma bonds with three by heating a mixture of
138.Match List I with List II and neighbouring carbon atoms). potassium chlorate and
select the correct answer using manganese dioxide than heating
the codes given below the Lists. potassium chlorate alone.
List I List II
2015 (I) Statement II Manganese dioxide
(Element) (Use) acts as a negative catalyst.
1. Time keeper in atomic Directions (Q. Nos. 146-148) The
A. Li
following three items consist of two _ (c) When a mixture of potassium chlorate
clocks and manganese dioxide is heated, more
B. Na 2. Batteries
statements, Statement I and amount of oxygen (O 2) is produced
C. K 3. Transfer of nerve
Statement II. You have to examine because here manganese dioxide
impulses these two statements carefully and (MnO 2) acts as a positive catalyst and,
select the answers to these items thus increases the rate of reaction.
D. Cs 4. Control of the water
content in the blood using the codes given below. So, option (c) is the correct answer.
143.Match List I with List II and The structure is called micelle. When _ (c) Mercury (Hg) is a heavy, silvery white
select the correct answer using washed with plenty of water, it goes with metal. The cohesive force is stronger
water, leaving behind a clean cloth. than the adhesive force. Hence, it does
the codes given below the Lists.
Whereas, a salt formation occurs only not stick to glass and as a result, it does
List I List II when acid and base react with each other. not wet. Mercury is the only metallic
(Compound) (Nature) element that is liquid at standard
146.The chemical used as a conditions of temperature and pressure.
A. Sodium hydroxide 1. Strong acid fixer/developer in photography is
B. Calcium oxide 2. Alkali (a) sodium sulphate 150.Permanent hardness of water is
C. Acetic acid 3. Weak acid (b) sodium sulphide due to the presence of
(c) sodium thiosulphate (a) sulphates of sodium and potassium
D. Hydrochloric acid 4. Base (b) sulphates of magnesium and calcium
(d) sodium sulphite
Codes (c) carbonates of sodium and
_ (c) Sodium thiosulphate (Na 2S 2O3) has magnesium
A B C D A B C D
the capacity to dissolve insoluble silver (d) bicarbonates of magnesium and
(a) 2 3 4 1 (b) 2 4 3 1
halides, so it is used in photography for calcium
(c) 1 4 3 2 (d) 1 3 4 2
fixing, i.e. to remove unreacted silver
_ (b) The correct matching is A-2, B-4, bromide as shown below _ (b) Chlorides and sulphates of
magnesium (Mg) and calcium (Ca) are
C-3, D-1 AgBr + 2Na 2 S 2O 3 → responsible for the permanent hardness
● Sodium hydroxide (NaOH) is an Sodium thiosulphate of water, as hardness due to them
inorganic compound. It is highly Na 3[Ag(s 2O 3 )2 ] + NaBr cannot be removed by just boiling.
caustic metallic base and alkali salt Sodium argento thiosulphate Note Bicarbonates of Mg and Ca lead to
of sodium.
temporary hardness which can be
● Calcium oxide (CaO) or quicklime is 147.Why is the graphite used in removed by boiling.
caustic alkaline solid at room electrolytic cells?
temperature. A chemical derivative of (a) Graphite is soft and can be easily 151.In the reaction,
calcium hydroxide of which moulded into electrodes ZnO + C → Zn + CO,
quicklime is the base anhydride. (b) Graphite is made up of layers of ‘C’ acts as a/an
● Acetic acid (CH 3COOH) is a weak carbon atoms which can be slide (a) acid (b) base
monoprotic acid. (c) Graphite is inert to most of the (c) oxidising agent (d) reducing agent
chemicals and remains intact in
● Hydrochloric acid (HCl) is a highly
electrolytic cells _ (d) Removal of oxygen (O) is reduction
corrosive, strong mineral acid with and its addition is oxidation. In the
many industrial uses. (d) Graphite is a good conductor of reaction, ZnO is reduced to Zn by C (i.e.
So, option (b) is the correct answer. electricity C causes its reduction) so, C acts as a
reducing agent.
144.All life forms contain ‘molecules _ (d) In graphite, each carbon atom is
bonded to three other carbon atoms in 152.Which one of the following are
of life’. These are the same plane giving a hexagonal array.
(a) carbohydrates (b) proteins the characteristics of organic
Atoms in the plane are bonded farming?
(c) nucleic acids (d) All of the above covalently, with only three of the four
potential bonding sites satisfied. 1. Use of chemical fertilizers to
_ (d) All life forms are made up of carbon, improve soil fertility.
hydrogen, oxygen, nitrogen, phosphorus The fourth electron is free to migrate in
and sulphur. Out of them, 97% the plane, that makes graphite 2. Frequent decomposing and
composition consist of C, H, O. electrically conductive. following.
A living cell contains inorganic materials That's why, graphite is a good 3. Use of herbs to control pests.
(minerals and water) and organic conductor of electricity. 4. Higher productivity per hectare.
materials like carbohydrates, lipids, Hence, it is used in electrolytic cells. Select the correct answer using the
proteins and nucleic acids. codes given below.
148.Washing soda is the common
(a) 1 and 4 (b) 1, 3 and 4
145.The cleansing action of soap and name for
(c) 2 and 3 (d) 2, 3 and 4
detergent in water is due to the (a) calcium carbonate
formation of (b) magnesium carbonate _ (d) Organic farming is a method of
(a) micelle (b) salt (c) sodium carbonate farming which primarily aimed at
(d) potassium carbonate cultivating the land and raising crops in
(c) base (d) acid
such a way, as to keep the soil alive and
(a) Soap and detergent both have a _ (c) Sodium carbonate (Na 2CO 3 ⋅ 10H 2O) in good health by use of organic wastes
water soluble polar end and fat soluble decahydrate, because of its cleansing
(crop, animal and farm wastes, aquatic
non-polar end. When it applied to a dirty property, also known by the name
wastes) and other biological materials
cloth, their non-polar parts surround the washing soda.
alongwith beneficial microbes
dirt (fat or oil) and the polar part remains Common name for calcium carbonate (bio-fertilizers) to release nutrients to
with water as shown below. (CaCO 3 ) is limestone, common name for
crops for increased sustainable
magnesium carbonate (MgCO 3 ) is
production in an ecofriendly, pollution
magnesia alba.
free environment.
149.Which one among the following Hence, statement I is incorrect.
does not wet the walls of the
glass vessel in which it is kept? 153.Which one among the following
(a) Water (b) Alcohol is used in making gunpowder?
(c) Mercury (d) Phenol (a) Magnesium sulphate
 29Cu =
61
(b) Potassium nitrate 157.Which of the following element Number of neutrons in 32
(c) Sodium stearate combinations will form ionic 30 Zn =
61
Number of neutrons in 31
(d) Calcium sulphate compounds? 2+
Number of neutrons in 60
30 Zn = 30
_ (b) Gun-powder is an intimate mixture of 1. Ca (Z = 20) and Ti (Z = 22) 59
nitrate, i.e. potassium nitrate (6 parts), So, 26 Fe contains the most neutrons.
2. Si (Z = 14) and Br (Z = 35)
charcoal (1 part) and sulphur (1 part).
Here, potassium nitrate (KNO3 ) behaves 3. Mg (Z = 12) and Cl (Z = 17) 161.Turpentine oil in paints is used
as a good oxidising agent. Sulphur and Select the correct answer using the as a
charcoal burn vigorously in the molten codes given below. (a) pigment
state of KNO 3. (a) Only 2 (b) Only 3 (b) film-forming material
(c) 2 and 3 (d) All of these (c) thinner
154.We use CFL to save electrical (d) drier
energy and to provide sufficient _ (b) An ionic bond is formed when one of
light. The full form of CFL is the atom can donate electron to achieve _ (c) Turpentine oil in paints is used as a
the inert gas electronic configuration and thinner. It act as a solvent. It can be used
(a) Condensed Filament Light
the other atom needs electrons to to thin oil paint to affect the flow of paint
(b) Compact Filament Lamp on to the canvas.
achieve the inert gas electronic
(c) Condensed Fluorescent Lamp
configuration. 162.The burning sensation of a bee
(d) Compact Fluorescent Lamp
Ionic bond is formed between metals sting can be stopped by rubbing
_ (d) The full form of ‘CFL’ is Compact and non-metals, i.e. Mg (metal) and
the affected area with soap. This
Fluorescent Lamp. It is a fluorescent Cl (non-metal) will form ionic compound
lamp designed to replace an but Ca (metal) and Ti (metal), is because
incandescent lamp. Si(non-metal) and Br (non-metal) will not (a) a bee sting is acidic and soap, an
form ionic compound. alkali, neutralises it
155.When heat rays are reflected (b) a bee sting is alkaline and soap, an
from the earth, gases like carbon 158.A thermodynamic process where acid, neutralises it
dioxide, nitrous oxide do not no heat is exchanged with the (c) soap cleans the affected area and
allow them to escape back to the surroundings is removes the sting
(a) isothermal (b) adiabatic (d) soap acts as an anaesthetic and
space causing our planet too heat
(c) isobaric (d) isochoric dulls the sensation
up. These gases are known as
(a) noble gas (b) greenhouse gas _ (b) In adiabatic process, there is no _ (a) Bee sting contains formic acid which
(c) hot gas (d) blue gas exchange of heat between the system leads to high burning sensation when
and the surroundings. Whereas, in bites. By placing large amount of alkali
_ (b) Greenhouse gases such as CO 2, isothermal process, temperature remains near the sting site is unlike to produce a
methane, nitrous oxide trap the heat constant. In isobaric process, change of perfectly neutral pH to stop the burning
radiated from earth. This leads to an state is brought at constant pressure and sensation.
increase in earth's temperature. This in isochoric process, volume of the
system remains constant.
163.What is the oxidising agent in
heating up of earth and its objects due to
the following equation?
the trapping of infrared radiation by 159.A compound X2O 3 contains
greenhouse gases in the atmosphere. HAsO 2 (aq) + Sn2 + (aq) + H + (aq)
31.58% oxygen by weight.
Greenhouse gases absorb and emit
The atomic mass of X is → As(s) + Sn4 + (aq) + H2O(l)
infrared radiation in the wavelength range −1
(a) 34.66 g mol (a) HAsO 2( aq )
emitted by earth.
(b) 45.01 g mol −1 (b) Sn2 + ( aq )
(c) 52.00 g mol −1 (c) H + ( aq )
2014 (II) (d) 104.00 g mol −1
(d) Sn4 + ( aq )
_ (c) In compound X 2O 3, _ (a) In the given reaction, HAsO 2(aq) is
156.A sample of carbon dioxide that
Percentage of oxygen by weight = 3158
. the oxidising agent that helps in the
undergoes a transformation
from solid to liquid and then to Percentage of X by weight = 68.42 oxidation of Sn2 + to Sn4+ and itself gets
Let the atomic mass of X = x reduced from +3 to 0.
gas would undergo
2x
(a) a change in mass × 100 = 68.42 164.Which one of the following
2 x + 48 substances is most likely to be
(b) a change in density
(c) a change in composition ∴ x = 52 used as soap?
(d) no change in physical properties So, atomic mass of X is 52 g mol − 1. (a) CH 3(CH 2 )12COOCH 3
_ (b) A sample of carbon dioxide that 160.Which one among the following (b) CH 3(CH 2 )5O(CH 2 )5CH 3
undergoes a transformation from solid contains the most neutrons? (c) CH 3(CH 2 )12COONa
to liquid and then to gas would undergo 59 61 (d) CH 3(CH 2 )12CHCI 2
(a) 26 Fe (b) 29Cu
a change in density. − +
61 60 2+
D=
M (c) 30 Zn (d) 30 Zn _ (c) CH 3(CH 2)12 COONa is most likely to
V
_ (a) Number of neutrons in an atom be used as soap. A soap is the sodium
During interconversion of the states, = Mass number − atomic number salt (or potassium salt) of a long chain
volume changes. Hence, density also
Number of neutrons in 59
26Fe = 33 carboxylic acid (or fatty acid).
changes.
165.A sample of gas is to be identified 169.If the reaction of 1.0 mole
by means of its behaviour in the NH3 (g) and 1.0 mole O 2 (g) 2014 (I)
presence of a glowing splint. 4NH3 (g) + 5O2 (g)
Which of the following gases will 172.Which of the following pairs
→ 4NO(g) + 6H2 O(l) is represents isoelectronic ions?
neither itself burn nor cause the
splint to burn?
carried to completion, then (a) Na + , K + (b) K +, Mg 2 +
(a) all the O 2(g) is consumed (c) Mg 2 +, Ca 2 + (d) Ca 2 +, S 2−
(a) Oxygen
(b) 4.0 moles of NO(g) is produced
(b) Nitrogen _ (d) Isoelectronic ions are the ions that
(c) Hydrogen (c) 1.5 moles of H 2O( I) is produced contain the same number of electrons.
(d) Methane (d) all the NH 3(g) is consumed Number of electrons in Na +
_ (b) Nitrogen is an inert gas neither itself _ (a) 4NH 3 ( g ) + 5O 2 ( g ) → = 11 − 1 = 10
4 mol 5 mol
burn nor cause the splint to burn. Number of electrons in K+ = 19 − 1 = 18
Oxygen does not burn itself but act as a 4NO ( g ) + 6H 2O( l )
(Na + , K+ ) are not isoelectronic ions.
supporter of combustion. 5
1 mole of NH 3 requires moles of O 2 Number of electrons in Mg 2+
Hydrogen helps in producing flames, 4
whereas methane helps in combustion = 1.25 mol = 12 − 2 = 10
and readily produces carbon dioxide. Since, for 1 mole of NH 3, 1.25 moles of (K+ ,Mg 2+ ) are not isoelectronic ions.
166.Heat given to a body which O 2 are required, therefore, O 2 is the Number of electrons in Ca 2+
limiting factor (here O 2 is only 1 mole).
raises its temperature by 1°C is = 20 − 2 = 18
Hence, all the O 2 will be consumed in
known as reacting with 1 mole of NH 3. (Mg 2+ , Ca 2+ ) are not isoelectronic ions.
(a) water equivalent Number of electrons in S 2−
(b) thermal capacity 170.The high heat of vaporisation of
= 16 + 2 = 18
(c) specific heat water is mainly a result of
(d) temperature gradient (a) van der Waals’ forces (Ca 2+ ,S 2− ) are isoelectronic ions.
(b) covalent bonds
_ (b) The heat capacity of a body is the 173.Dihydrogen can be prepared on
quantity of heat required by the body to (c) interionic attraction
a commercial scale by the action
raise its temperature by 1°C. It is also (d) hydrogen bonding
of steam on hydrocarbons, when
termed as thermal capacity.
_ (d) The heat of vaporisation is often a mixture of CO and H2 gas is
167.Consider the following reaction, quoted for the normal boiling formed. It is known as
temperature of the substance. In the
xAs2 S3 + yO 2 → molecule of liquid, water are held (a) water gas (b) producer gas
zAs2O3 + w SO2 together by relatively strong hydrogen (c) industrial gas (d) fuel gas
What is y (the coefficient for O2 ) bonding. High value of heat of _ (a) Water gas is a synthesis gas,
when this equation is balanced vaporisation shows the presence of containing CO and H 2.
using whole number coefficients? stronger forces of attraction. H 2 O + C → H 2 + CO
(a) 5 (b) 7 171.A monoatomic species that has Producer gas is a fuel gas, i.e.
(c) 9 (d) 11 18 electrons and a net charge of manufactured from material such as coal.
_ (c) Balanced chemical equation is 2− has 2C + O 2 + 3.73N 2 → 2CO + 3.73 N 2
2 As 2 S 3 + 9O 2 → 2As 2O 3 + 6SO 2 (a) the same number of electrons as a 174.Which one of the following
So, y is 9. neutral argon atom statements about hydrogen
(b) more protons than electrons
168.How many grams of MgCO 3 is/are correct?
(c) 2 unpaired electrons
contain 24.00 g of oxygen? (d) 20 protons 1. Hydrogen has three isotopes of
which protium is the most
(The molar mass of MgCO3 is _ (a) A monoatomic species has the same common.
84.30 g mol −1) number of electrons as a neutral argon
2. Hydrogen ion (H + ) exists freely
atom.
(a) 42.15 g (b) 84.30 g
The monoatomic species must be S 2 − .
in the solution.
(c) 126.00 g (d) 154.00 g 3. Dihydrogen (H2 ) acts as a
Monoatomic Number of reducing agent.
_ (a) In MgCO 3, there are 3 oxygen atoms species electrons
in each mole. Select the correct answer using the
Sulphur (S) 16 codes given below :
Atomic mass of oxygen is 16 g/mol. So,
there are Sulphur ion (S 2− ) 16 + 2 = 18 (a) Only 1 (b) 1 and 3
(16 × 3) = 48 grams of oxygen in one (c) Only 3 (d) All of these
Argon (Ar) 18
mole of MgCO 3
_ (b) 1. Hydrogen has three isotopes;
Molar mass of MgCO 3 = 84.30 g mol −1 Hence, from above table, it is clear that protium (11 H), deuterium ( 21H or D)
S 2 − have same number of electrons as
48 g of O 24 g O and tritium (13H or T ).
= neutral argon atom. So, a monospecies
84.3 MgCO 3 x g MgCO 3 that has 18 electrons and net charge of 2. Hydrogen ion (H+ ) does not exist
2 − has the same number of electrons as freely in the solution. It combines with
x = 42.15 g a neutral argon atom. anion present in solution.
 3. Dihydrogen (H 2) acts as a reducing 180.The latest discovered state of form hydrogen ions and the conjugate
agent and helps in the reduction. matter is base ions when dissolved in water.
Hence, statements 1 and 2 are correct (a) solid Commonly used mineral acids are
and statement 3 is incorrect. (b) Bose-Einstein condensate sulphuric acid, hydrochloric acid and
(c) plasma nitric acid. Citric acid, ascorbic acid and
175.Which one of the following tartaric acid are organic acids.
statements is correct? (d) liquid
(a) Fullerenes have only six-membered _ (c) There are four states of matter, which 184.Which one of the following is
are given solid, liquid, gas and plasma. correct regarding the reaction of
carbon rings Plasma is the latest discovered state of
(b) Fullerenes are cage-like molecules matter. This state of matter exists at very
fluorine with water?
(c) Diamond is thermodynamically the high temperature. 2F2 ( g) + 2H2O(l) → 4H + (aq)
most stable allotrope of carbon
(d) Graphite is slippery and hard and is 181.The mass number of an atom is + 4F − (aq) + O 2 ( g)
therefore, used as a dry lubricant in determined by (a) Fluorine is oxidised to F −
machines (a) adding the number of neutrons and (b) Water is oxidised to O 2
number of electrons (c) Water is reduced to H +
_ (b) Fullerenes consist of 20 hexagonal (d) Oxidation state of fluorine does not
and 12 pentagonal rings. They are the (b) adding the number of protons and
cage-like molecules. number of electrons change
Diamond is kinetically most stable (c) the number of protons only _ (b) In this reaction, water is oxidised to
allotrope of carbon. (d) adding the number of neutrons and O 2. Its oxidation state changes from −2
Graphite is soft, smooth and slippery number of protons to 0.
and is therefore, used as a dry lubricant
in machines.
_ (d) Mass number is defined as the sum of 185.Which one of the following
the number of protons and neutrons in an is/are amphoteric?
So, option (b) is the correct answer. atom of the element. It is denoted by A.
(a) Al(OH) 3(s) and Fe(OH) 3(s)
A = p+ n
176.The number of valence electrons (b) Al(OH) 3(s) and HCO −3 (aq)
where, p = number of protons
in the O2− ion is (c) Ba(OH) 2(s) and NaOH(aq)
n = number of neutrons
(a) 4 (b) 6 (c) 8 (d) 10 (d) Only Al(OH) 3(s)
182.Consider the following balanced
_ (c) The number of valence electrons in _ (d) Aluminium hydroxide [Al(OH)3 ] is an
2−
the O ion is 8. chemical equation, amphoteric substance. It can acts as
O(atomic number) = 8 = 1s 2 2 s 2 2 p4 2CO + O 2 s2CO 2 either a Bronsted-Lowry base or a Lewis
O 2− ion = 1s 2 2 s 2 2 p6 Which one of the following acid.
Outermost shell has valence electrons.
statements is significant in Al(OH)3 + 3H+ → Al 3+ + 3H 2O
Al(OH)3 + OH − → Al(OH)4−
177.Which one of the following is relation to the above chemical
the correct electronic equation? 186.The most of the mass of an
configuration of chlorine? (a) One can add to a vessel only atom can be found in
(a) 2, 7, 8 (b) 2, 8, 7 2 moles of CO for each moles of (a) electrons (b) charges
(c) 2, 8, 8 (d) 7, 8, 9 O 2 is added (c) nucleus (d) electron cloud
(b) No matter how much of these two
_ (b) We know that, reagents are added to a vessel, _ (c) The atomic mass of an atom can be
Atomic number of chlorine = 17 found in nucleus. For atoms, the protons
So, its electronic configuration = 2, 8, 7. 1 mole of O 2 is consumed and neutrons of the nucleus account for
(c) When they react, CO reacts with almost all of the mass. Atomic mass
178.The number of aluminium ions O 2 in a 2 : 1 mole ratio figures refer to an individual particle
present in 54 g of aluminium (d) When 2 moles of CO and 1 mole of species.
(atomic weight = 27) is O 2 are placed in a vessel, they will
react to give 1 mole of CO 2 187.A fertilizer contains 20%
(a) 2 (b) 18
nitrogen by mass. To provide a
(c) 1.1 x 10 24 (d) 1.2 x 10 24 _ (c) According to the given reaction, fruit tree with an equivalent of
2 moles of carbon dioxide can form only
_ (d) Number of aluminium ions present in when 2 moles of carbon monoxide reacts 1 kg of nitrogen, the quantity of
54 g of aluminium
with 1 mole of oxygen. The formation of fertilizer required is
6.023 × 10 23 × 54
= product always depends on the (a) 20 kg (b) 0.20 kg
27 availability of reactant. (c) 0.05 kg (d) 5 kg
= 1.2 × 10 24
183.Which of the following acids is a _ (d) Mass per cent
179.The most stable form of carbon is mineral acid? Mass of nitrogen
= × 100
(a) diamond (b) graphite (a) Citric acid Mass of fertilizer
(c) fullerene (d) coal (b) Hydrochloric acid 1
⇒ 20 = × 100
(c) Ascorbic acid x
_ (a) The most stable form of carbon is (d) Tartaric acid
diamond because in its structure, 100
⇒ x = = 5 kg
directional covalent bonds are present _ (b) A mineral acid (or inorganic acid) is 20
throughout the lattice. an acid derived from one or more Required quantity of fertilizer = 5 kg
inorganic compounds. All mineral acids