1

EAMS DREAMS
TNSTITUTE
Dreams Institute HSTITUTE
(Atoms &Molecules
1. The atomicities of ozozne. sulphur, phosphorus
and argon are respectively:
a) 8.3.4 and 1
b) 1.3,4, and 8 a) 8.3,4 3 b) 1,3.4. nr
c) 4.1.8 and 3 c) 4.1.8 G 3
d) 3.8.4and 1
d)3,8.4

2. The symbol of a metal element which is used in

making thermometers is:
a) Ag b) Hg b) Hg
a) Ag c) Me d) Sg
c) Mg d) Sg

3. The latin language name of an element is

natrium. The English name of this element is:
a) sodium b) potassium a) HH b ) e n c) Aarsta d) iua
C) magnesium d) sulphur
4. 4ea4 u a g furs fen gT I f 3
4.The atomic theory of matter was proposed by:
a) John Kennedy b) Lavoisier
c) Proust d) John Dalton a) Ho dist b)8 a c) e d) Has 3v25
5. One of the following elements has an atomicity
of :one. This element is:
a) Helium
c)sulphur
b) hydrogen
d) ozone
33
a)isH b) JeRS c)aiua d ) s
6. The English name of an element is potassium,
its Latin name will be:
a) plumbum b) cuprum
c) Kalium d) natrium
a)1H b)f c)asH d)
7. The law of conservation of mass was given by:
a) Dalton b) Proust
c) Lavoisier d) Berzelius a) 3 c 5

8. The element baving atomicity four' is most d) eikg

ikely to be:
a) argon b) fluorine
c) phosphorus d) francium a) a s b)E d s c) THeOH d)zd
9. If 14 g of calciurm oxide is formed by the
NaTes dsa radse e
complete decomposition of calcium carbonate, 9. 1.4 H TA
then the amount of calcium carbonate taken and
the amount of carbon dioxide formed will be
respectively:
a) 2.2 g and 1.l g
b) 1.1gand 2.5 g a) 2.2 g 3 1.lg b) .I g B 25g
c) 2.5 g and 1.I g
d) 5.0 g and I.I g c)2.5g 31lg d)5.0g Silg

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10. The faw of constant proportions was given by: frsra
a) Proust
10.
a er hs fon err fër fam
b) Iavoisier
c) Dalton a) E b ) rerrtnra c) Tse d) aAfrga
d) Berzelius
11. rs, arTdan, nsaa w fquez I qra
11. Oot of ozone, phosphorus, sulphur and krypton,
the elements having the lowest and highest
atomicities are respectively: a) aira nr3 fruers b) fgre nr s
a) sulphur and krypton
c) andaR 3 aira d) fres n3 ua
b) krypton and ozone
c)phosphonus and sulphur 12. fea nm fere ave
d) krypton and sulphur
a) 10 mm b) 10 cm c) 10 cm d) 10m
12. One nm is equal to
a) 10 mm b) 10 cm 13. g fefarwfrs fat s e *
c) 10 cm d) 10 m
13.The scientist who proposed the first letter (or
first letter and another letter ) of the Latin or
English name of an element as its symbol, was:
a) 3sE5 b) Ae
a) Dalton d) HEHe
b) Proust
c) Lavoisier
d) Berzerlius

14. The atoms of which of the following pair of

elements are most likely to exist in free state ?
a) hydrogen and helium
b) argon and carbon
c) neon and nitrogen
d) helium and neon

15. Which of the following elements has the same

molecular mass as its atomie mass?
a) nitrogen
b) neon b) s c) »rains d) adcs
c) oxygen
a) e r s
d) chlorine

16. In water, the proportion of oxygen and

bydrogen by massis: a) 1:4 b) 1:8 c) : 1 d) 8: 1
a) 1:4 b): 8
c)4:1 d) 8:1
17. Jres vards (H202) fëE. A gWT
17. In bydrogen peroxide (H202), the proportion of
bydrogen by mass is:
a) 1:8 b) 1:16 c) 8: 1 d) 16: 1
a) I:8
b) 1:16
8:1
d)16:1 18. fereTN r a f qTT s

18.Tbe symbols of the elements cobalt, aluminium,

helium and sodium respectively written by a student
are as follows. Which symbol is the correct one? d)
a) CO b) AL c)
a) CO b) AL
) He d) So

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19. The atomic number of an element X is 13. What

19. f s x vnrz if 13 fere res x3
will be the number of electrons in its fon Xx*"?
a) I b) 15
a) 11 b)115 c) 16 d))10
c) 16 d) 10

20. Which of the following represents a correct 20. fears f frar rt areza arae earge
chemical formula ?
a) CaCl b) Na,N
a) CaCI b) NasN c) NaSO d} NaS
c) NaSO, d) NaS
21. f fer zafia fedaes t f r 10 3 s
21.If the number of electrons in an ion Z3- is 10, the
atomic number of element Z will be:
a) 7 b) 5 c) .10 d) 8
a) 7 b) 5
c) i d) 8
22. fat as aGs fës a
22. The anion of an element has:
a) more electrons than the normal atom
b) less electrons than the nomal atom
c) more protons than the normal atom
d) same number of electrons as normal atom

25, fsgs G
23. A particle X has 17 protons, 18 neutrons 23.f E X fës 17 18 18

and 18 electrons. This particle is most likely

tobe: a) fe Sa5 b) anion c) d)
a) a cation b) an anion
c) a molecule d) sulphur 24. fea 3 fAoa 2,4 m 6 t YeSA3
24. An element which can exhibit valencies of
2.4 and 6 can be: a) 3 b)o c d) J 4
a) copperT b) iron
c) mercury d) sulphur 25. fa i3 EVaHg Af 16 ài fere »res
25. The atomic number of an element E is 16.
The number of electrons in its ion E* will be: a) 16 b)18 c) 15 d)
a)16 b) 18
c) 15 d) 14 26. fat 33 è ids fëo er d

26. The cation of an element has

a) the same number of electrons as its neutral
atom
b) more electrons than a neutral atom

c)less protons than ä neutural atom

d) less electrons than a neutral atom

27. Two elements X and Y have valencies of 5

27. 3 an Trå qHe5 3 «3 3 3
and 3, and 3 and 2, respectively. The elenments
X and Y are most likely to be respectively:
a) copper and sulphur
b) sulphur and iron a) 3 E arua
c) phosphorus and niuogen
d) nitrogen and iron

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28. The number of electrons in an ion Y" is 28. f wes y2 fës feiaer a i r 10. 3
10. The atomic number of element Y is most
likely to be:
a) 8 b) 12
c) 10 d) 14
a) 8 b) 12 c) d) 14

29. A particle P has 18 electrons, 20 neutrons

29. a P ëo 18 fedaes, 20 fsts 19
and 19 protons. This particle must be:
a) a molecule b) a binary compound
c) an anion d) a cation
a)fa b a r t fmaE
c) anion d) a cation
30. An ionic compound will be formed by the
combination of one of the following pairs of
elements. This pair of elements is
a) chlorine and calcium
b) calcium and sodium
c) sulphur and carbon
d) chlorine and chlorine

31. Moiecular compounds are usually formed

by thecombination between
a) a metal and a non-metal
b) two different non-metal
c) two different metals
d) any two gaseous elements

32. The formula of a compound is X3Y. The

valencies of elements X and Y will be
respectively a) 33 b) 3 3 1 c)2S 3 d)3 *3 2
a) 1 and 3 b) 3 and 1
c) 2 and 3 d) 3 and 2
33.a 33 x2 Hsee e TaH X2 (S04) 3 d.
33. The formula of the sulphate of an element X is
a) XN b) XN2 c) XN d) X
X,(SO)3 The formula of nitride of element X will
be
a) XN b) XN2
c) XN d) X2
a) 10 TH deADH S 12 apH Harsia
34. Which of the following pair of elements
represents a mole ratio of 1:1 ? )12 a Barstai »s6 aH Ts5
a) 10 g of calcium and 12 g of magnesium c)12 H arTN5 M 20 aH sEHH
b) 12 g of magnesium and 6 g of carbon
c) 12 g of carbon and 20 g of calcium d) 20 aH s H N3 20 arH dsznai
d) 20 g of sodium and 20 g of calcium
35. feos fee fao 360 a Yå Ho a
35. Which of the following correctly represents
360 gram of water ?
i) 2 moles of H,O ii) 20 moles of water i) H0 2 Rs
ii) 6.022 x 10 molecules of water ii) 6.022 x 102, 4ret e E
iv) 1.2044 x 10 molecules of water
a) (1) iv) 1.2044 x 10 u t e we
b) (i) and (iv) b) (i) 3 (iv)
a) (i)
iandiu)
c)) 3 (ii) d) (i) 3 (iv)

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36. A 32 a aira fës a n tzH , 32
36. If 32 g of sulphur has x atoms,
then the number
be
of atoms in 32 g of oxygen will
:

a) u2 b) 2
a) 2 b) 2r c)r d) 4x
d) 4r
c)x
37. fea feferat HaT N3 r a s i 2
atoms each
37. A student wants to have 3.011x 10 er isr
of magnesium and carbon
Elements for this 3.011 x 1032 YaHE ~T Fger à
purpose. he will have to weigh:
carbon
a) 24 g of magnesium and 6 g of
b) 12 g of carbon and 24 g of magnesium a) 24 aH arsrEH »6a T a 5
c) 20 g of magnesium 10 g of carbon
d) 12 g of magnesium and 6 g of carbon b) 12 TH a3a5 ¥3 24 a a r s H
c) 20 a arsttH 10 aH r 5
and 16
38. The ratio of atoms in 12 g of magnesium
d) 12 3H arstainH MG 6 JH T a 5
gof sulphur will be b) 4:3
a)3:4 aiva è ës
c)1:1 d) 1:2 38. Harstani è 12 a 16 a

39. If 12 gram of carbon has x atoms, then the 1:2

d)
number of atoms in 12 grams of magnesium will be:
a) 3:4 b) 4:3 c) : 1
a) X b) 2x
c) 2 d) 1.5x 39. A 12 i aaas fea man »a Js, 3* 12

40. Which of the foliowing has the maximum of

atoms? a) b)2 c)2
d 1.5
a) 18 g of H,O b) 18 g of 0
c) 18 g of CO d) 18 g of CHA
a) 18 g of H,0 b) 18 g of O,
d) 18 g of cHs
c) 18 g of co,

Answer Key
3. a 4 d
1. d
6. c 8. C 9 d 10.
. b
11. d 12. b 13. d 14. d
17. b 18. 19. d 20 b
16. d 25..b
21. a 22. a 23. b 24. d
29. d 0
26. d 27. d 28 b
34. b 35d
33
31. b 32. a 39 0.
36. b 37. d 38.