JEE Chemistry States Of Matter MCQs Set B

Question. The correct value of the gas constant ‘R’ is close to
(a) 0.082 litre-atmosphere K^–1 mol^–1
(b) 0.082 litre-atmosphere K
(c) 0.082 litre – atmosphere^–1 K mol^–1
(d) None of these

Answer: A

Question. Pure hydrogen sulphide is stored in a tank of 100 litre capacity at 20° C and 2 atm pressure. The mass of the gas will be
(a) 282.68 g
(b) 282 g
(c) 340 g
(d) 28.24 g

Answer: A

Question. At N.T.P the volume of a gas is found to be 273 ml. What will be the volume of this gas at 600 mm of Hg and 273°C?
(a) 691.6 ml
(b) 391.8 ml
(c) 380 ml
(d) 750 ml

Answer: A

Question.  Gas equation PV = nRT is obeyed by
(a) Both
(b) Only adiabatic process
(c) Only isothermal process
(d) None of these

Answer: A

Question. The total pressure of a mixture of two gases is
(a) the sum of the partial pressures
(b) the difference between the partial pressures
(c) the product of the partial pressures
(d) the ratio of the partial pressures

Answer: A

Question. Dalton’s law of partial pressure will not apply to which of the following mixture of gases
(a) H₂ and Cl₂
(b) CO₂ and Cl₂
(c) H₂ and SO₂
(d) None of these

Answer: A

Question. Pressure exerted by saturated water vapour is called
(a) Aqueous tension
(b) Total pressure
(c) Partial pressure
(d) None of these

Answer: A

Question. The pressure exerted by 6.0g of methane gas in a 0.03 m³ vessel at 129°C is (Atomic masses : C = 12.01, H = 1.01 and R = 8.314 JK^–1 mol ^–1)
(a) 41648 Pa
(b) 215216 Pa
(c) 31684 Pa
(d) 13409 Pa

Answer: A

Question.  A gaseous mixture was prepared by taking equal mole of CO and N₂. If the total pressure of the mixture was found 1 atmosphere, the partial pressure of the nitrogen (N₂) in the mixture is
(a) 0.5 atm
(b) 0.9 atm
(c) 0.8 atm
(d) 1 atm

Answer: A

Question. A bubble of air is underwater at temperature 15°C and the pressure 1.5 bar. If the bubble rises to the surface where the temperature is 25°C and the pressure is 1.0 bar, what will happen to the volume of the bubble ?
(a) Volume will become greater by a factor of 1.6
(b) Volume will become greater by a factor of 1.1.
(c) Volume will become smaller by a factor of 0.70.
(d) Volume will become greater by a factor of 2.5.

Answer: A

Question. A mixture contains 64 g of dioxygen and 60 g of neon at a total pressure of 10 bar. The partial pressures in bar of dioxygen and neon are respectively (atomic masses O = 16, Ne = 20)
(a) 4 and 6
(b) 5 and 5
(c) 6 and 4
(d) 8 and 2

Answer: A

Question. 500 mL of air at 760 mm pressure were compressed to 200 mL. If the temperature remains constant, what will be the pressure after compression?
(a) 1900 mm
(b) 2000 mm
(c) None of these
(d) 1500 mm

Answer: A

Question. Value of universal gas constant (R) depends upon
(a) None of these
(b) Temperature of gas
(c) Volume of gas
(d) Number of moles of gas

Answer: A

Question. 56 g of nitrogen and 96 g of oxygen are mixed isothermally and at a total pressure of 10 atm. The partial pressures of oxygen and nitrogen (in atm) are respectively
(a) 6, 4
(b) 5, 5
(c) 4, 6
(d) 2, 8

Answer: A

Question. If 10^–4 dm³ of water is introduced into a 1.0 dm³ flask at 300 K, how many moles of water are in the vapour phase when equilibrium is established ?
(Given : Vapour pressure of H2O at 300 K is 3170 Pa; R = 8.314 J K^–1 mol^–1)
(a) 1.27 × 10^–3 mol
(b) 1.53 × 10^–2 mol
(c) 5.56× 10^–3 mol
(d) 4.46 × 10^–2 mol

Answer: A

Question. Which among the following has lowest surface tension ?
(a) Hexane
(b) Water
(c) CH₃OH
(d) None of these

Answer: A

Question. The total pressure of a mixture of two gases is
(a) the sum of the partial pressures
(b) the difference between the partial pressures
(c) the product of the partial pressures
(d) the ratio of the partial pressures

Answer: A

Question. Ideal gas equation is the combination of
I. Boyle's law
II. Charles's law
III. Avogadro law
IV. Dalton's law of partial pressure
Choose the correct option.
(a) I, II and III
(b) I, III aor IV
(c) Only I and II
(d) II and III

Answer: A

Question. According to the kinetic theory of gases, in an ideal gas, between two successive collisions a gas molecule travels
(a) in a straight line path
(b) in a wavy path
(c) with an accelerated velocity
(d) in a circular path

Answer: A

Question. Gases consist of large number of identical particles (atoms or molecules) that are so small and so far apart on the average that the actual volume of the molecules is negligible in comparison to the empty space between them. Above given statement explain which property of gases ?
(a) Compressibility of gases
(b) None of these
(c) Gases has fixed shape
(d) Gases occupy all the space available to them

Answer: A

Question. If there were loss of kinetic energy, the motion of gas molecules will _____A _______ and gas will ____B______.
(a) A = stop, B = settle down
(b) A = increase, B = collide
(c) A = decrease, B = get liquified
(d) None of these

Answer: A

Question. Which of the following assumption of kinetic molecular theory states that gases do not have fixed shape ?
(a) Particles of a gas are always in constant and random motion.
(b) Particles of a gas move in all possible directions in straight line
(c) Total energy of molecules before and after the collision remains same
(d) None of these

Answer: A

Question.  Which of the following assumption of kinetic theory if hold good than the pressure vs volume graph of experimental data (real gas) and that of theoretically calculated from Boyle's law (ideal gas) should coincide ?
(i) There is no force of attraction between the moleculesof a gas.
(ii) Volume of the molecules of a gas is negligibly small in comparison to the space occupied by the gas.
(a) (ii) only
(b) None of these
(c) (i) only
(d) Both (i) and (ii)

Answer: A

Question. Kinetic theory of gases proves
(a) All of these
(b) only Charles’ law
(c) only Boyle’s law
(d) only Avogadro’s law

Answer: A

Question. Which one of the following is the wrong assumption of kinetic theory of gases ?
(a) All the molecules move in straight line between collision and with same velocity
(b) Molecules are separated by great distances compared to their sizes.
(c) Pressure is the result of elastic collision of molecules with the container’s wall.
(d) Momentum and energy always remain conserved.

Answer: A

Question. When is deviation more in the behaviour of a gas from the ideal gas equation PV = nRT ?
(a) At low temperature and high pressure
(b) At high temperature and low pressure
(c) At high temperature and high pressure
(d) At low temperature and low pressure

Answer: A

Question. In van der Waal’s equation of state of the gas law, theconstant ‘b’ is a measure of
(a) volume occupied by the molecules
(b) intermolecular attraction
(c) intermolecular repulsions
(d) intermolecular collisions per unit volume

Answer: A

Question. The values of van der Waal’s constant ‘a’ for the gases O₂, N₂, NH₃ and CH₄ are 1.360, 1.390, 4.170 and 2.253 L² atm mol^–2 respectively. The gas which can most easily be liquified is
(a) NH3
(b) O2
(c) N₂
(d) CH₄

Answer: A

Question. A gas described by van der Waal’s equation
(i) behaves similar to an ideal gas in the limit of large molar volume
(ii) behaves similar to an ideal gas in the limit of large pressure
(iii) is characterised by van der Waal's coefficients that are dependent on the identity of the gas but are independent of the temperature
(iv) has the pressure that is lower than the pressure exerted by the same gas behaving ideally
(a) (i) and (iii)
(b) (ii) and (iv)
(c) (i) and (ii)
(d) (i), (ii) and (iii)

Answer: A

Question. The units of constant a in van der Waal’s equation is
(a) dm6 atm mol^–2
(b) dm atm mol^–1
(c) dm3 atm mol^–1
(d) atm mol^–1

Answer: A

Question. The van der Waal’s constant ‘a’ for four gases P, Q, R and S are 4.17, 3.59, 6.71 and 3.8 atm L2 mol–2 respectively. Therefore, the ascending order of their liquefaction is
(a) Q < S < P < R
(b) R < P < S < Q
(c) Q < S < R < P
(d) R < P < Q < S

Answer: A

Question. The gas with the highest critical temperature is
(a) CO₂
(b) He
(c) H₂
(d) N₂

Answer: A

Question. A gas is said to behave like an ideal gas when the relation PV/T = constant. When do you expect a real gas to behave like an ideal gas ?
(a) When the temperature is high and pressure is low
(b) When both the temperature and pressure are high
(c) When both the temperature and pressure are low
(d) When the temperature is low

Answer: A

Question. An ideal gas can’t be liquefied because
(a) forces between its molecules are negligible
(b) it solidifies before becoming a liquid
(c) Its molecules are relatively smaller in size
(d) its critical temperature is always above 0°C

Answer: A

Question. Above Boyle point, real gases show ______X______ from ideality and Z values are _______Y_______ than one.
(a) X = Positive deviation, Y = Greater
(b) X = Positive deviation, Y = Less
(c) X = Negative deviation, Y = Greater
(d) X = Negative deviation, Y = Less

Answer: A

Question. Select the one that when used would be considered as best condition for liquification of a gas
(a) Increasing the pressure and decreasing the temperature.
(b) Decreasing the pressure
(c) Increasing the temperature
(d) Decreasing the pressure and increasing the temperature

Answer: A

Question. At 1 atm pressure boiling temperature is called _____X___. If pressure is 1 bar then the boiling point is called _____Y____ of the liquid.
(a) X = Normal boiling point, Y = Standard boiling point
(b) X = Critical boiling point, Y = Normal boiling point
(c) X = Critical boiling point, Y = Standard boiling point
(d) X = Standard boiling point, Y = Normal boiling point

Answer: A

Question. Which of the following statement is incorrect ?
(a) 1 atm pressure is slightly less than 1 bar pressure
(b) Standard boiling point of liquid is slightly lower than the normal boiling point.
(c) The normal boiling point of water is 100°C and its standard boiling point is 99.6°C
(d) None of the above

Answer: A

Question. A liquid can exist only
(a) between boiling and melting temperature
(b) between melting point and critical temperature
(c) at any temperature above the melting point
(d) between triple point and critical temperature

Answer: A

Question. The kinetic energy of molecules in gaseous state is
(a) more than those in the liquid state
(b) less than those in the liquid state
(c) equal to those in the liquid state
(d) less than those in solid state

Answer: A

Question. The correct order of viscosity of the following liquids will be
(a) dimethyl ether < methyl alcohol < water < glycerol
(b) glycerol < dimethyl ether < water < methyl alcohol
(c) methyl alcohol < glycerol < water < dimethyl ether
(d) Water < methyl alcohol < dimethyl ether < glycerol

Answer: A

Question. The liquid which has the highest rate of evaporation is
(a)   petrol
(b) water
(c) nail-polish remover
(d) alcohol

Answer: A

Question. In which phenomena water changes into water vapour below its B.P. ?
(a) Evaporation
(b) Boiling
(c) Condensation
(d) No such phenomena exist

Answer: A

Question. The surface tension of which of the following liquid is maximum?
(a) H₂O
(b) C₂H₅OH
(c) CH₃OH
(d) C₆H₆

Answer: A

Question. When the temperature increases, the viscosity of
(a) gases increases and viscosity of liquids decreases
(b) gases decreases and viscosity of liquids increases
(c) gases and liquids increases
(d) gases and liquids decreases

Answer: A

Question. A drop of oil is placed on the surface of water. Which of the following statement is correct ?
(a) It will spread as a thin layer
(b) It will remain on it as a sphere
(c) It will be partly as spherical droplets and partly as thin film
(d) It will float as a distorted drop on the water surface

Answer: A

Question. Which of the following phenomena is caused by surface tension ?
(a) All of the above
(b) Small drops of mercury from spherical bead instead of spreading on the surface
(c) A liquid rise in a thin capillary
(d) Particles at the bottom of river remain separated but they stick together when taken out

Answer: A

Question. The spherical shape of rain-drop is due to
(a) surface tension
(b) None of these
(c) density of the liquid
(d) atmospheric pressure

Answer: A

Question. Which of the following statement(s) is/are true for London force ?
(i) These forces are always attractive.
(ii) These forces are important for long distance too.
(iii) Their magnitude depends on the polarisability of the particle.
(a) (i) and (iii)
(b) (i) only
(c) (i) and (ii)
(d) (iii) only

Answer: A

Question. A pin or a needle floats on the surface of water, the reason for this is
(a) surface tension
(b) upthrust of liquid
(c) less weight
(d) None of the above

Answer: A

Question. Choose the correct sequence of T and F for following statements. Here T stands for true and F stands for false statement.
(i) Dipole - dipole forces act between the molecules possessing permanent dipole.
(ii) Partial charge possessed by these dipoles is always equal to unit electronic charge.
(iii) Dipole - dipole interaction is weaker than London forces and ion - ion interaction
(a) TFF
(b) TFT
(c) TTF
(d) TTT

Answer: A

Question.  Which of the following statements are correct ?
(i) Hydrogen bonding is a special case of dipole - dipole interaction.
(ii) Energy of hydrogen bond varies between 10 to 100 kJ mol^–1.
(iii) Hydrogen bonds are powerful force in determining the structure and properties of compounds like proteins, nucleic acids etc.
(iv) Strength of the hydrogen bond is determined by the coulombic interaction between the lone-pair electrons of the electronegative atom of one molecule and the hydrogen atom of other molecule.
(a) All of these
(b) (i), (ii) and (iii)
(c) (i) and (ii)
(d) (ii), (iii) and (iv)

Answer: A

Question.  Which of the following statements are correct regarding the characteristic of gases ?
(i) Gases are highly compressible.
(ii) Gases exert pressure equally in all directions.
(iii) Gases have much higher density than the solids and liquids.
(iv) Gases mix evenly and completely in all proportion without any mechanical aid.
Choose the correct option.
(a) (i), (ii) and (iv)
(b) (i), (ii) and (iii)
(c) (ii), (iii) and (iv)
(d) (i), (ii), (iii) and (iv)

Answer: A

Question.  Choose the correct sequence of T and F for following statements. Here T stands for true and F stands for false.
(i) There may be exchange of energy between colliding molecules, their individual energies may change, but the sum of their energies remains constant.
(ii) At any particular time, different particles in the gas have different speeds and hence different kinetic energies.
(iii) Particles of a gas move in all possible directions in straight lines. During their random motion, they collide with each other and with the walls of the container.
(iv) In kinetic theory it is assumed that average kinetic energy of the gas molecules is directly proportional to the absolute temperature.
(a) TTTT
(b) TFTT
(c) TTTF
(d) TFFT

Answer: A

Question. Choose the correct sequence of true and false for following statements. Here T represents true and F represents false statement.
(i) Greater the viscosity, the more slowly the liquid flows.
(ii) Glass is an extremely viscous liquid.
(iii) Viscosity of liquid increases as the temperature rise.
(a) TTF
(b) FFT
(c) TFF
(d) TFT

Answer: A

Question. Assertion : Three states of matter are the result of balance between intermolecular forces and thermal energy of the molecules.
Reason : Intermolecular forces tend to keep the molecules together but thermal energy of molecules tends to keep them apart.
(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
(b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(c) Assertion is correct, reason is incorrect
(d) Assertion is incorrect, reason is correct

Answer: A

Question. Assertion : Gases expand and occupy all the space available to them
Reason : There is no force of attraction between the particles of a gas at ordinary temperature and pressure
(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
(b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(c) Assertion is correct, reason is incorrect
(d) Assertion is incorrect, reason is correct

Answer: A

Question. Assertion : Gases do not liquefy above their critical temperature, even on applying high pressure.
Reason : Above critical temperature, the molecular speed is high and intermolecular attractions cannot hold the molecules together because they escape because of high speed.
(a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
(b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
(c) Assertion is correct, reason is incorrect
(d) Assertion is incorrect, reason is correct

Answer: A