Kinetic Theory of Gases

Q. The volume occupied by $1.8g$ of water vapour at $374$ °C and $1bar$ pressure will be:-
$[R=0.083barL{K}^{-1}mo{l}^{-1}]$

1. 96.66 L
2. 55.87 L
3. 3.10 L
4. 5.37 L

Q.

Prove that the kinetic energy of a gas is directly proportional to the absolute temperature of the gas.

Q. At $363K$, the vapour pressure of $A$ is $21$ $kPa$ and that of $B$ is $18$ $kPa$. One mole of $A$ and $2$ moles of $B$ are mixed. Assuming that this solution is ideal, the vapour pressure of the mixture is $kPa$. (Round off to the nearest integer).

Q. Liquid $A$ and $B$ form an ideal solution at temperature $T$. Mole fraction of $A$ in liquid and vapor phase are $0.4$ and $\frac{4}{13}$ respectively, when total pressure is $130\text{torr}$. The vapor pressure (in torr) of $A$ and $B$ in pure state at temperature $T$ are respectively

1. $100,200$
2. $200,100$
3. $100,150$
4. $150,100$

Q. Calculate the kinetic energy (in joule) for $8.00\text{g}$ of methane at ${27}^{\circ }\text{C}$.

Q.

On the basis of kinetic theory of gases, the gas exerts pressure because its molecules

1. suffer a change in momentum when impinging on the walls of the container.

2. continuously stick to the walls of the container.

3. continuously lose their energy till it reaches the wall.

4. are attracted by the walls of the container.

Q.

An ideal gas in a closed container is slowly heated. As its temperature increases, which of the following statements are true?

(A) the mean free path of the molecules decreases.

(B) the mean collision time between the molecules decreases.

(C) the mean free path remains unchanged.

(D) the mean collision time remains unchanged.

1. $\left(B\right)and\left(C\right)$

2. $\left(A\right)and\left(B\right)$

3. $\left(C\right)and\left(D\right)$

4. $\left(A\right)and\left(D\right)$

Q.

Oxygen is present in a 1 litre flask at a pressure of $7.6\times {10}^{-10}$ mm Hg. Calculate the number of oxygen molecular in the flask at $0^{\circ }C$.
A. $2.7\times {10}^{10}$
B.$4.7\times {10}^{10}$
C.$2.7\times {10}^{23}$
D. $5\times {10}^{37}$

Q.

The average distance travelled by the molecule between successive collision is called _____.

1. Collision path

2. Mean free path

3. Collision diameter

4. Collision distance

Q. Define collision frequency.

Q.

What is the kinetic energy of a gas?

Q.

Gaseous states have the lowest kinetic energy.

1. True
2. False

Q.

A gas occupies a volume of 2.5 L at $9\times {10}^{5}N{m}^{-2}$. Calculate the additional pressure required to decrease the volume of the gas to 1.51. Assume temperature is constant.

1. 15*10⁵ N m^-2

2. 9*10⁵ N m^-2

3. 6*10⁵ N m^-2

4. 24*10⁵ N m^-2

Q. Which of the following statements is not correct in terms of kinetic theory of gases?

1. Gaseous particles are considered as point masses
2. The molecules are in random motion
3. When molecules collide, they lose energy
4. When a gas is heated, the molecules move faster

Q. The average kinetic energy (in joules) of molecules in $8.0\text{g}$ of methane at ${27}^{\circ }\text{C}$ is:

1. $6.21\times {10}^{-21}\text{J/molecule}$
2. $6.21\times {10}^{-22}\text{J/molecule}$
3. $3.1\times {10}^{-22}\text{J/molecule}$
4. $6.21\times {10}^{-20}\text{J/molecule}$

Q.

Why does pressure increase when the volume decreases?

Q. The pressure needed to confine 1.5 mole of $N_2$ molecules to 28 L flask is 1.0 bar. Thus, root mean square velocity of the gas (assuming ideal behaviour) is

1. $200{\text{m s}}^{-1}$
2. $370{\text{m s}}^{-1}$
3. $51.5{\text{m s}}^{-1}$
4. $37.0{\text{m s}}^{-1}$

Q. A gas is heated in such a way that its pressure and volume both become double. Now by decreasing temperature, some of air molecules were introduced into the container to maintain the increased volume and pressure. Assuming ${\frac{1}{4}}^{th}$ of the initial number of moles has been given for this purpose. By what fraction of temperature has been raised finally of initial absolute temperature.

1. $\frac{16}{7}$times
2. $\frac{16}{5}$ times
3. $\frac{8}{5}$ times
4. $\frac{4}{5}$times

Q. An $LPG$ cylinder contains gas at a pressure of $300kPa$ at ${27}^{\circ }$C. The cylinder can withstand the pressure of $1.2\times {10}^{6}Pa$. The room in which the cylinder is kept catches fire. The minimum temperature at which the bursting of cylinder will take place is ____ ${}^{\circ }$C. (Nearest Integer)
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Q. Write the postulates of "kinetic theory of gases' .

Q.

When a molecule of a gas collides with the wall of a container, it gets a rebound and the momentum transferred to the wall is equal to

Q.

Does ideal gas exist in reality?

Q.

Small drops of liquid are spherical in shape due to

1. density of liquids

2. surface tension

3. vapor pressure

4. Joule Thomson effect

Q.

For the given isotherm for one mole of an ideal gas, which follows Boyle's law, what will be the value of temperature.

1. $947\text{K}$
2. $1220\text{K}$
3. $48\text{K}$
4. $8.2\text{K}$

Q. The mean free path of the molecules of a certain gas at $300\text{K}$ is $2.6\times {10}^{-5}\text{m}$. The collision diameter of the molecule is $0.26\times {10}^{-9}\text{m}$. Calculate (a) the pressure of the gas and (b) the number per unit volume of the gas.

1. $5.306\times {10}^2\text{Pa}$ and $4.183\times {10}^{23}{\text{m}}^{-3}$
2. $10.6\times {10}^2\text{Pa}$ and $1.281\times {10}^{23}{\text{m}}^{-3}$
3. $5.306\times {10}^2\text{Pa}$ and $1.281\times {10}^{23}{\text{m}}^{-3}$
4. $5.306\times {10}^2\text{Pa}$ and $2.798\times {10}^{23}{\text{m}}^{-3}$

Q. Which of the following is incorrect statement for an ideal gas ?

1. When temperature increases at constant pressure, collision frequency increases
2. Mean free path decreases by increasing temperature at constant pressure
3. If all gas molecules are assumed to be rigid sphere of negligible volume, the only possible molecular motion is translation
4. Kinetic energy decreases by increasing pressure at constant temperature

Q.

Easily liquefiable gases show larger deviations from gas laws. Comment on this statement on the basis of kinetic molecular theory.

Q.

Collision diameter and mean free path all related as:

1. Inversely proportional

2. Equal

3. Not related

4. Directly proportional

Q. Calculate the kinetic Energy in Joules of 8gm of Methane at ${27}^{\circ }$C. (R = 8.32)

1. 
2. 
3. 
4. 

Q.

Which of the following state has maximum energy?

1. ice

2. water

3. steam

4. all have the same energy.