1000+ State of Matter MCQ for UPSC CDS [Solved]

1. If the temperature and pressure remain unchanged the volume of $O_2$obtained by the decomposition of a certain volume of $S{O}_2$ will be
A. Triple the volume of $S{O}_2$
B. Half the volume of $S{O}_2$
C. Equal to the volume of $S{O}_2$
D. One third the volume of $S{O}_2$
Answer : C

2. Boltzmann constant is given by
A. R
B. R+N
C. R:N
D. R-N
Answer : C

3. In a unit cell of cesium chloride the arrangement of cesium ions is
A. face centred cubic
B. hexagonal close packed
C. body centred cubic
D. simple cubic
Answer : C

4. In what ratio by mass carbon monoxide and nitrogen should be mixed so that partial pressure exerted by each gas is same?
A. $m\left(N_2\right)=m\left(CO\right)$
B. $m\left(N_2\right)=2m\left(CO\right)$
C. $m\left(N_2\right)=0.5m\left(CO\right)$
D. None of these
Answer : A

5. In the wurtzite structure sulphur atoms have
A. cubic arrangement
B. hexagonal dose packed arrangement
C. body centred arrangement
D. None of these
Answer : B

6. The pressure of the ideal gas is less than the real gas because of the
A. increase in the number of collisions
B. volume occupied by the molecules
C. inter-molecular attraction
D. finite size of molecules
Answer : C

7. The mean free path of a gas molecule is the distance
A. between the two opposite walls of the container
B. through which the molecules travel in one second
C. through which molecules move between two consecutive collisions
D. travelled by all the molecules divided by the total number of molecules in a particular gas
Answer : C

8. What will be the mass of 6.023 x ${10}^{23}$ molecules of carbon monoxide?
A. 14 gm
B. 28 gm
C. 16 gm
D. 44 gm
Answer : D

9. Number of molecules of carbon dioxide present in 44 gm $C{O}_2$ is
A. 12 x ${}^{{10}^{23}}$ approximately
B. 3 x ${ }^{{10}^{10}}$ approximately
C. 6 x ${ }^{{10}^{10}}$ approximately
D. 3 x ${}^{{10}^{23}}$ approximately
Answer : C

10. Which of the following will have low heat of fusion?
A. a molecular solid
B. an ionic solid
C. a metallic solid
D. a network of covalent solid
Answer : A

11. A chalk box exhibits
A. cubic geometry
B. monoclinic geometry
C. orthorhombic geometry
D. tetragonal
Answer : A

12. Three dimensional array of points in space is called
A. unit cell
B. crystal lattice
C. micro-crystal
D. None of these
Answer : A

13. At what temperature, the root mean square velocity of oxygen molecules is equal to that of $S{O}_2$ at 27°C?
A. 150°C
B. 150°K
C. 27°C
D. None of these
Answer : B

14. Indicate the most viscous liquid of the following
A. propanol-2
B. 1.2, ethandiol
C. 1.2,3 propentriol
D. ethanol
Answer : C

15. Which of the following is an amorphous solid?
A. NaCl
B. $Ca{F}_2$
C. Diamond
D. Glass
Answer : D

16. In the ideal gas equation PV = nRT constant 'R' has the unit
A. joule
B. litre/mol
C. lit-atm/deg/mol
D. calorie/mole
Answer : C

17. Kinetic theory of gases postulates :
A. The molecules in a gas are in stationary state
B. The molecules in a gas exert appreciable attraction on each other
C. The molecules move in a random motion with widely different velocities
D. The molecules in a gas collide against each other as well as the wall of the container, but do not change their direction of motion
Answer : C

18. One gram molecule of a gas at N.T.P occupies 22.4 litres. This fact was derived from
A. Benjamin hypothesis
B. Avogadro's hypothesis
C. Dalton's theory
D. Law of atomic volume
Answer : C

19. The number of atoms per unit cell in bcc arrangement is
A. 1
B. 4
C. 3
D. 2
Answer : D

20. The weight of 22.4 litres of any gas at N.T.P. represent its
A. gm atomic weight
B. gm molecular weight
C. gm equivalent weight
D. None of these
Answer : B

21. Which of the following methods is used to determine the atomic weight?
A. Victor Meyer's method
B. Dumas' method
C. Cannizaro's method
D. None of these
Answer : C

22. For a given gas at temperature T and pressure P the root mean square velocity (RMS) is C; then at temperature T and pressure 3P the RMS is
A. Unchanged
B. 3C
C. C/3
D. $C^3$
Answer : A

23. In the gas equation PV = xT, x is a constant. The value of the constant depends upon
A. the quantity of gas
B. the quality of gas
C. type values of T and P
D. None of these
Answer : A

24. In anti-fluorite structure the negative ions
A. occupy tetrahedral voids
B. occupy octahedral voids
C. are arranged in ccp
D. are arranged in hcp
Answer : C

25. The ratio of RMS velocity to average velocity of a gas molecule at a particular temperature is
A. 1.086:1
B. 1:1.086
C. 2 :1.086
D. 1.086 : 2
Answer : A

26. At 303 K ethanol has a vapour pressure of about 0.118 atm., acetic acid has the vapour pressure of about 0.039 atm., and ethyl iodide has a vapour pressure of about 0.263 atm. Which of the following represents the correct order of increasing normal boiling point ?
A. $C{H}_{3}COOH<C_2{H}_{5}OH<C_2{H}_{5}I$
B. $C_2{H}_{5}I<C{H}_{3}COOH<C_2{H}_{5}OH$
C. $C_2{H}_{5}I<C_2{H}_{5}OH<C{H}_{3}COOH$
D. $C_2{H}_{5}OH<C_2{H}_{5}I<C{H}_{3}COOH$
Answer : C

27. The critical temperature of a substance is defined as
A. the temperature above which the substance decomposes
B. the temperature above which the substance can exist only as a gas
C. melting point of the substance
D. boiling point of the substanc
Answer : B

28. The radii of $A^{+}$ and $X^{-}$ are 95 pm and 181 pm respectively. Coordination number of $A^{+}$ is expected to be
A. 8
B. 6
C. 4
D. 3
Answer : B

29. Volume occupied by 1 gm equivalent of oxygen at NTP is
A. 22.4 litres
B. 2.24 litres
C. 5.6 litres
D. 11.2 litres
Answer : C

30. Which of the following is an example of covalent network solid?
A. Sodium
B. Solid carbon dioxide
C. Sodium chloride
D. Silicon
Answer : D

31. Arrange the following in order of increasing inter-molecular forces and boiling points:$N{H}_3$,He,$C{l}_2$
A. $He<C{l}_2<N{H}_3$
B. $He>C{l}_2>N{H}_3$
C. $C{l}_2<He<N{H}_3$
D. $N{H}_3<He<C{l}_2$
Answer : A

32. 5.At a given temperature and pressure 2 volumes of A combine with 5 volumes of B to form 2 volmes of C and 1 volume. A combine with one volume of B to form 2 volumes of D. The formula of C is
A. $A_3{B}_6$
B. $\sqrt{AB}$
C. $A_2{B}_5$
D. $A{B}_5$
Answer : B

33. Certain volume of a gas exerts on its walls some pressure at a particular temperature. It has been found that by reducing the volume of the gas to half its original value, the pressure becomes I twice that the initial value of constant temperature. This happens because
A. More number of a gas molecules strike the surface per second
B. Velocity of the gas molecules increases
C. Gas molecules attract each other
D. Weight of the gas increase with volume
Answer : C

34. The vapour density of a gas is 11.2. The volume occupied by 2.4 g of the gas at S.T.P wil be
A. 2.4 litres
B. 3.6 litres
C. 2.24 litres
D. 11.2 liters
Answer : D

35. Cubic close packed arrangement of ions is described as
A. ABC AB ABC.....
B. ABC ABC......
C. AB AB..........
D. ABC CBA...
Answer : B

36. How many moles of water are present in 180 gm. of water ?
A. 11
B. 5
C. 90
D. 21
Answer : D

37. Of the following properties, the magnitude of one must always increase with temperature. The property is
A. vapour pressure
B. density
C. $∆H_{vap}$
D. surface tension
Answer : A

38. According to Avogadro's hypothesis equal volumes of two gases under the same conditions of temperature and pressure contain
A. Equal number of electrons
B. Equal number of ions
C. Equal number of atoms
D. Equal number of molecules
Answer : D

39. How many nearest neighbours are there in an octahedral hole of a close packed structure
A. 4
B. 6
C. 8
D. 12
Answer : B

40. The weight of 11.2 litres of $C{O}_2$ at S.T.P. would be
A. 22 gms
B. 66 gms
C. 11 gms
D. 16 gms
Answer : D

41. The V.D. of a gas is 11.2 gm. The volume occupied by 11.2 gm. of this gas at N.T.P. is
A. 12 litre
B. 11.2 litres
C. 2.24 litres
D. 22.4 litres
Answer : A

42. Four 1 litre flasks are separately filled with hydrogen, helium, oxygen and ozone gases at the same temperature and pressure. The ratio of total number of atoms of these gases present in the different flasks would be
A. 1:1:1:1
B. 1:2:2:3
C. 2:1:2:3
D. 3:2:2:1
Answer : C

43. The number of molecules in 32 gms of oxygen in
A. 6.02 x ${}^{{10}^{10}}$
B. 3.2 x ${}^{{10}^{23}}$
C. 6.02 x ${}^{{10}^{22}}$
D. 32 x ${}^{{10}^{10}}$
Answer : A

44. When there is more deviation in the behaviour of a gas from ideal gas equation PV = nRT
A. at high temperature and low pressure
B. at low temperature and high pressure
C. at high temperature and high pressure
D. at low temperature and low pressure
Answer : B

45. How many nearest neighbours are there in an atom or ion in an octahedral hole of a close packed structure?
A. 4
B. 6
C. 8
D. 18
Answer : B

46. 7.Which of the following sets of conditions represent the easiest way to liquefy a gas?
A. Low temperature and high pressure
B. High temperature and low pressure
C. High temperature and low pressure
D. None of these
Answer : A

47. The number of atoms per unit cell in simple cubic, face centred cubic and body centred cubic arrangement are, respectively
A. 8,14,9
B. 1,2,4
C. 1,4,2
D. 8,4, 2
Answer : C

48. The vapour density of completely dissociated sociated $N{H}_{4}CL$ would be
A. Determined by the amount of solid $N{H}_{4}CL$ used in the experiment
B. Triple to that of $N{H}_{4}CL$
C. Half of that $N{H}_{4}CL$
D. Slightly less than half of that of $N{H}_{4}CL$
Answer : C

49. In which one of the following does diffusion occur most rapidly?
A. Solid
B. Liquid
C. Gases
D. Gels
Answer : C

50. The number of molecules is 4.25 g of ammonia are approximately
A. 3.5 x ${}^{{10}^{23}}$
B. 2.5 x ${}^{{10}^{23}}$
C. 1.5 x ${}^{{10}^{23}}$
D. 0.5 x ${}^{{10}^{23}}$
Answer : D