Chemistry Notes

1. Chemical formula for Lime water is – Ca (OH)2

2. The pH of lemon juice is around – 2
3. What are Metalloids?----Modern Periodic Table, a zig-zag line separates metals from non-
metals. The borderline elements boron, silicon, germanium, arsenic, antimony, tellurium and polonium are
intermediate in properties and are called metalloids.

4. Which is used in plastics- -Ethylene

5. Symbol for Methane is –CH4
6. What is the freezing point of water on Kelvin scale----273.15K
7. A solution reacts with chalk powder to give a gas that turns lime-water milky. The solution
contains--- HCl
8. The ability of metals to be drawn into thin wires is called--- Ductility
9. Which gas is known as 'noble gas'?---The elements Helium, Neon, Argon,Krypton, Xenon
and Radon of group 18 in the periodic table are called as Noble gases or Rare gases.
10. Which acid is present in the ant sting- - - -Methanoic acid (Formic acid)
11. Which is a similarity between acids and bases----Process of mixing acid or base with water is
exothermic
12. Which contains CFC- -Refrigerants
13. Litmus solution is derived from----Lichen
14. Elements in the modern periodic table are arranged in vertical columns—18
15. Which type of coal has the highest percentage of carbon--Anthracite
16. Covalent bonds are formed by the sharing of electrons between two atoms so that both can achieve a
completely filled----------------------shell-Outermost
17. Kerosene oil rises up in a wick of lantern because of-----Capillarity
18. Each element has a name and-------------A unique chemical symbol
19. Which is the process of converting sugar into alcohol- - -Fermentation
20. Lactic acid is a----Three-carbon molecule
21. Biogas is an excellent fuel as it contains up to 75%-Methane
22. ------are known as electronegative elements because they form negatively charged ions by the gain
of electrons----
Non-metals
23. The addition of which adds fizz to soft drinks----Carbon dioxide
24. Being light and non-inflammable gas is used to blow balloons- - - -Helium
25. Which acid is the constituent of eyewash----Boric acid
26. Formaldehyde is used in----Perfumes
27. Lime water turns milky on passing carbon dioxide gas through it due to the formation of-----CaCO3
28. Which methods can be used for separating a mixture of NaCl and NH4Cl-- Sublimation
29. Name the sodium compound which is used to permanently remove the hardness of water-Sodium
carbonate
30. What is the scale for measuring a hydrogen ion concentration in a solution-pH scale
31. What is another name for calcium oxide-- Quick lime
32. Name the German chemist who grouped elements into triads in 1817- Wolfgang Dobereiner
33. Which is a property of an ionic compound----It has a high melting point and boiling point
34. Which elements is a liquid at room temperature- -Mercury & Bromine
35. Which is an ester- - - -CH3COOC2H5
36. The Modern Periodic Table based on of the elements----Atomic Number
37. What element is a greenish yellow gas with a characteristic smell at room temperature-Chlorine
38. Silver ornaments become black after some time when exposed to air because - Silver reacts with
sulphur in the air to form silver sulphide
39. The four essential requirements for photosynthesis include- Chlorophyll, sunlight, carbon dioxide
and water
40. What is the mineral name of rock salt --- Halite
41. The chemical name of blue vitriol is---Copper sulphate
42. Which scientist invented the periodic table---Dmirtri Mendeleev
43. Which air pollutants is known as soot-----Particulate matter
44. The chemical composition of the ruby gemstone is- - -Aluminium oxide
45. What is the chemical symbol of Lead-----Pb
46. In periodic table as one goes down the group, which property doesn’t change- - -Valency.
47. The process of forming a thick layer of aluminium oxide on the surface of aluminium so as to
protect it from corrosion is called Anodising

48. The Big Bang theory was propounded by-- - -George Lamaitre
49. The process of browning of paper in old books is known as- - -Foxing
50. Name the gas which is filled in wick-type lighters-----Butane
51. Chlorophyll contains which element----Magnesium
52. The amount of radiation being emitted by a radioactive material is measured using the conventional
unit----Curie
53. Muscovite , pegmatite and biotitie are ores of----Mica
54. Zinc sulfate heptahydrate (ZnSO4.7H2O) is commonly known as-----White viriol
55. Which acid is used in the anodizing process Dilute sulphuric acid
56. Diamonds can be synthesized by subjecting pure carbon to----Very high pressure and high
temperature
57. gas, released from chloroflurocarbons, is harmful to the ozone layer- - -Chlorine
58. The number of valence electrons in a graphite atom is----four
59. The best method to dispose of biological wastes from hospitals is----Incineration
60. How many neutrons are present in protium- - -0
61. The full form LPG is – Liquified Petroleum Gas
62. Which in the air turns silver articles black (when exposed to air)- -Sulphur
63. Which gas is found in soda water –-- Carbon dioxide
64. The compound of a metal found in nature is called----Mineral
65. Settling down of heavier insoluble components of a mixture of water and insoluble substances is
called -sedimentation
66. Name the scientist who proposed that electrons are embedded in a positive sphere --– JJ Thomson
67. Which elements is a versatile element that forms the basis for all living organisms and many of the
things we use-----Carbon
68. Which can be used for purification of water------Alum
69. is the first synthetic fibre made by man-----Nylon
70. Which organic compounds have suffix ‘al’-----Aldehydes
71. What is the atomicity of Phosphorous-- - -Tetra-atomic
72. Which chemicals/gases is/are responsible for causing the greenhouse effect Water vapour,CO2
and CFCs
73. A solution of weak acid and its salt is called – Buffer solution
74. Isotopes are atoms that have the----Same atomic number but different atomic mass
75. Which radioisotope is used for the treatment of metastatic bone cancer----Strontium-89
76. If a lit candle is covered with a glass tumbler, the flame gets extinguished after some time. What
is the reason for this Due to limited oxygen the covered candle got extinguished after
some time
77. Which polymer is used for the manufacturing of water pipes- - - -PVC
78. What is the IUPAC name of glycerol-----Propane-1,2,3-triol
79. What is the ore of aluminium called-----Bauxite
80. What is the electronic configuration of rhodium----1s2 2s6 2p6 3s2 3p6 3d104s2 4p6 4d8 5s1
81. One Carbon credit contains----1000 kg of carbon dioxide
82. Which noble gas is radioactive in nature- - - -radon
83. Bleaching powder is used for- - -Disinfecting water
84. Power alcohol is a mixture of----Petrol and ethyl alcohol
85. A flame is made up of three parts: the innermost part and the outermost part. Why is the innermost
part black----Because of the presence of un-burnt carbon particles
86. Which is the first element on the periodic table-----Hydrogen
87. Which one is a copper ore- - -Malachite
88. Which determines that a chemical reaction has not taken place- -Change in size
89. What is the melting point of the tungsten filament used in bulbs--3422o C

90. Photosynthesis takes place in the presence of light. Which colour’s light range least
affects the rate of Photosynthesis –---Green

91. Which metal is used in electroplating on iron to protect it from corrosion and
formation of rust-Zinc
92. Clean development mechanism programme is used to reduce-------Greenhouse gas emission
93. Decomposition of calcium carbonate to calcium oxide and carbon dioxide on heating is an example
of-Thermal decomposition reaction
94. Brass is a mixture of------30% zinc and 70% copper
95. The most common isotopes used in a nuclear weapon are of-----Uranium and plutonium
96. The fibres, such as nylon and polyester, that are made from chemical substances are called-
Synthetic fibres
97. Name one alkaline solution- - - -Sodium hydroxide
98. Which is the greenish yellow gas with a characteristic smell at room temperature- - -Chlorine
99. Name one of amphoteric oxide----Zinc oxide (Examples of amphoteric oxides are zinc oxide and
aluminiumoxide.)
100. Depending upon carbon and moisture content which is the highest and lowest quality of coal
respectively---Anthracite, lignite
101. Ethanol is formed during- - - -Anaerobic respiration in yeasts
102. What do we call a positively charged ion-----cation
103. What do we call a negatively charged ion- -anion
104. What term is used to denote intermixing of particles of two different types of matter on their
own-----Diffusion
105. Name the elements that are present in baking powder----Sodium, hydrogen, carbon and
oxygen
106. Which product is formed due to burning of a magnesium ribbon with a spirit lamp
Magnesium oxide
107. Name some non-biodegradable materials- Plastic, DDT,Bakelite
108. A sucrose molecules contains carbon atoms 12
109. Fullerene is an allotropic form of Carbon
110. What is the relative molecular mass of water 18 u

111. The position of an element in the periodic table is determined by its number----Proton
112. What is the chemical formula of propane-C3H8
113. The natural aging of a lake by nutrient enrichment of its water is termed as-----Eutrophication
114. To neutralize the effect of formic acid injected by ant bit, which can be used-Sodium
bicarbonate
115. Synthetic fibres catch fire easily, however, the uniforms of fireman have a coating of plastic
to make them flame resistant-Melamine
116. The term ‘Isotope’ refers to - Elements having same atomic number but different mass
number
117. Homogenous mixture of a solute and a solvent is called----Solution
118. Which gas can be fixed in the atmosphere by lightning-----Nitrogen
119. Which minerals is obtained from veins and lodes----Major metallic minerals like tin, copper,
zinc and lead etc. are obtained from veins and lodes.
120. What is the average temperature of the surface water of the oceans-17 degree Celsius
121. The reaction between an acid and a base is known as-Neutralisation
122. Silver bromide used in----Black and white Photography
123. The process of melting that is change of solid state into liquid state is known as- -Fusion
124. State of matter can be changed into another state by changing the-----Temperature
125. The heat energy required to convert a solid into a liquid or vapour, or a liquid into a
vapour,without change of temperature known as-Latent heat
126. The unit of pressure is-----Pascal
127. A change of state directly from solid to gas without changing into liquid state is called
Sublimation
128. Direct change of gas to solid without changing into liquid is called----Deposition.
129. The number of atoms constituting a molecule is known as----Atomicity.
130. Electron was discovered by----JJ Thomson
131. Proton was discovered by- - -Rutherford
132. The ratio by number of atoms for water is H:O------2:1.
133. The ratio of hydrogen and oxygen by mass in water is----1:8
134. Neutrons are present in the nucleus of all atoms, except-----Hydrogen
135. Maximum number of electrons present in a shell is given by the formula-----2n2
136. Who suggested the distribution of electrons into different orbits of an atom?----Bohr and Bury
137. The stranger gas is- - - -Xenon
138. Ammonia (NH3) is synthesized through Haber‘s process
139. Egg shell is made up of------Calcium Carbonate
140. Fuse wire is made up of----Lead and Tin
141. Acid rain is caused when the air is polluted by------Nitrous Oxide &Sulphur dioxide
142. Ozone is allotrope of-----oxygen
143. The chemical that is used in making artificial rain is-----Silver nitrate.
144. What is the ratio of HNO3 and HCl in aqua regia?- -1:3
145. The hardest substance available on earth is------Diamond
146. The nature of saliva is-----Acidic.
147. Bee Sting contains a----Methanoic Acid
148. The impurity present in the ore is called as-----Gangue
149. Lightest element in the universe is- - -Hydrogen
150. Quicksilver is another name of------Mercury
151. Chemical name of Green vitriol is----Iron sulphate
152. Bhopal gas Tragedy of 1984 is related to-----Methyl Isocyanate
153. The lowest temperature at which a substance catches fire is called its-----Ignition temperature.
154. The substances which have very low ignition temperature and can easily catch fire with a flame
are called ----Inflammable substances
155. A chemical process in which a substance reacts with oxygen to give off heat is called
Combustion
156. The amount of heat energy produced on complete combustion of 1 kg of a fuel is called its ---
Calorific value.
157. Galvanization is a method of protecting steel and iron from rusting by coating them with a thin
layer of ----Zinc.
158. Hydrogen gas is not evolved when a metal reacts with----Nitric acid.
159. Why are sodium and potassium kept in kerosene oil?-----Metals such as potassium and
sodium react so vigorously that they catch fire if kept in the open. Hence, to protect them and to
prevent accidental fires, they are kept immersed in kerosene oil.
160. Which Metal is the Best Conductor of Electricity?----Silver
161. The property of metals by which they can be beaten into thin sheets is called----Malleability
162. The ability of metals to be drawn into thin wires is called-----Ductility.
163. Which is the most ductile metal known?- - - -Gold
164. Which chemical is known as king of chemicals?----Sulfuric acid
165. The atmosphere of Venus is made up of thick white and yellowish clouds of- - -Sulphuric acid
166. Petrol and diesel are obtained from a natural resource called------Petroleum.
167. Graphite is a good conductor of heat and electricity because it has----Free electrons
168. Electrons present in the outermost shell of an atom are known as----Valence electrons
169. Invar is an alloy of-- - -Iron and Nickel
170. Sterling silver is an alloy of- - -Silver and copper
171. Gun metal is an alloy of--------Copper ,tin and zinc
172. Farmers neutralise the effect of acidity of the soil by adding-----slaked lime
173. Lime water reacts with chlorine to give- - - -CaOCl2(Bleaching powder)
174. The process of reduction involves----Addition of hydrogen
175. Oxidation is a process which involves----Addition of oxygen
176. Formula of Nitrous oxide-----N2O
177. Formula of Nitrogen dioxide------NO2
178. An organic compound containing −COOH functional group is called-----Carboxylic acid
179. –CHO represents the functional group------Aldehydes
180. An organic compound containing −OH functional group is called-------Alcohol
181. Which elements are considered the metalloids?-----Boron (B), Silicon (Si), Germanium
(Ge),Arsenic (As),Antimony (Sb),Tellurium (Te),Polonium (Po).
182. What happens to the electropositive character of elements on moving from left to right in a
periodic table----Decreases
183. Name of the most reactive element present in group 17 (Halogens)- -Fluorine
184. Newlands relation is called------Law of Octaves
185. The elements of group 16 are called-----Chalcogens
186. The group 17 elements are also known asHalogens
187. Which chemical compound is also known as 'Oil of Vitriol'?-----Sulphuric Acid (H2SO4)
188. Calcium sulphate dihydrate (CaSO4 .2H2O) is commonly known as---Gypsum
189. Calcium oxide (Cao) is commonly known as------Quick lime
190. Calcium hydroxide (Ca(OH)2 ) is commonly known as-------Slaked lime
191. Trichloro Methane( CHCl3 ) is commonly known as- - -Chloroform
192. Calcium Carbonate (CaCo3) is commonly known as----Chalk
193. Calcium sulfate hemihydrate (CaSO4⋅ 1/2H2O) is popularly known as plaster of Paris
Plaster of Paris
194. Name the acid present in Orange------Citric acid
195. Name the acid present in Tamarind-----Tartaric acid
196. Name the acid present in Tomato------Oxalic acid
197. Name the acid present in Apple------Malic acid
198. Metals are found on the------Left-hand side of the Periodic Table.
199. Non-metals are found on the------Right-hand side of the Periodic Table
200. How many periods and groups are present in the periodic table------7 periods and 18 groups
201. Which group elements are called transition metals-----Group number 3 to 12
202. At the time of Mendeleev, the number of elements known was-----63
203. The value of Avogadro’s constant is ---- 6.022 × 1023
204. Which radioactive element is used in the treatment of cancer-----Cobalt-60
205. The condition produced by aerial oxidation of fats and oils in foods marked by unpleasant
smell and taste is called- Rancidity
206. The important ore of aluminium is-----Bauxite
207. Percentage of lead in lead pencils is------Zero
208. An emulsion is a colloid of a------Liquid in a liquid
209. Vulcanization of rubber is carried out by adding-----Sulphur
210. Which gas is used as fire extinguisher-----Carbon dioxide
211. Water can be separated from alcohol water mixture by-----Distillation
212. Petroleum is a mixture of-----hydrocarbons
213. Curd is sour due to presence of-----Lactic acid
214. Milk is a natural------Emulsion
215. Impure camphor is purified by------sublimation
216. Which is the most abundant metal in the Earth’s crust----Aluminium
217. Solder is an alloy of-----Tin, lead
218. Liquified Petroleum gas (LPG) is a mixture of-----Butane and Propane
219. The earthy impurities like sand, rocks and limestone present in an ore is called----Gangue.
220. Atoms of the elements having same atomic number, but different mass numbers are known as
Isotopes

221. A reaction in which oxidation and reduction takes place simultaneously is-----Redox Reaction

222. What is the name of the reaction in which acid reacts with base to form salt and water
Neutralisation reaction
223. What is "milk of magnesia” chemically-----Magnesium hydroxide
224. Silk fibre chemically is-----Protein
225. Process of gaining electrons is known as----Reduction
226. According to Newlands’ Law of Octaves, how many elements exist in nature-----56
227. What is the atomicity of sulphur---Poly-atomic
228. Which inert gas mixed with oxygen is given to the patients suffering from restricted breathing?
Helium
229. Who is known as “Father of modern chemistry’?-------Antotne Lavoisier
230. Name the metal that can be easily cut with a knife------Lithium, Sodium, Potassium
231. The molecular formula of Propane is------C3H8
232. According to .........., the properties of elements are a periodic function of their atomic masses
-----Mendeleev's Periodic Law
233. Which is the last element in Newlands’ Law of Octaves?-------Thorium
234. C12 H22 O11 is also known as---Sugar
235. What is the chemical name of the Laughing Gas?-Nitrous oxide
236. Nail polish remover contains?-------Acetone
237. Black lung disease occurs in people working in-----coal mine
238. Which coal is known as the ‘brown coal’-----Lignite
239. What is commonly called limestone is ----- calcium carbonate (CaCO3)
240. Dry ice is----solid carbon dioxide
241. The acid used in eyewash is-- - -Boric acid
242. Hydrochloric acid is also known as-----Muriatic acid
243. Water gas is the mixture of-----Carbon monoxide & hydrogen
244. What is the formula for lime water?--------Ca(OH)2
245. What is the pH level of blood of a normal person? 7.35-7.45
246. The main source of Naphthalene is---------Coal-tar
247. Non-stick kitchenware are coated with-----Teflon
248. The trip of the match-stick contains--------red phosphorus
249. The non-metal found in the liquid state is--bromine
250. Which acid is used to remove ink stain?- - -Oxalic acid
251. Metals causes Itai -Itai disease---------------Cadmium
252. The chemical name of ‘Common salt’ is- Sodium chloride
253. The chief constituent of natural gas is----Methane
254. Paraffin wax used for making candles is obtained from-----Petroleum