Question 1 :
A gas has a molecular diameter of 0.1 m. It also has a mean free path of 2.25 m. What is its density?<br>

Question 2 :
The average energy per molecule of a triatomic gas at room temperature T is?

Question 3 :
Assertion: Vibrational energy of diatomic molecule corresponding to each degree of freedom is ${ k }_{ B }T$. Reason: For every molecule, vibrational degree of freedom is 2.

Question 4 :
The average kinetic energy of a molecule of a perfect gas is :

Question 6 :
The nature of the graph of pressure 'P' against reciprocal&#160;of volume 'V' of an ideal gas at constant temperature is&#160;

Question 7 :
Which of the following is correct?<br>(Internal pressure in Van der Waal's equation)

Question 8 :
The value of gas constant $R$ (in cal/mol-K) for hydrogen is :

Question 9 :
The number of degrees of freedom for each atom of a monoatomic gas is :

Question 10 :
If we heat the particle at one end of a material,

Question 11 :
A gas in a 1 $m^3$ container has a molecular diameter of 0.1 m. There are 10 molecules. What is its mean free path?<br>

Question 12 :
The speed of sound in hydrogen at NTP 1270 m/s. Then, the speed in a mixture of hydrogen and oxygen in the ratio 4 : 1 by volume will be :

Question 13 :
Internal energy of $n_{1}$ moles of hydrogen at temperature $150\ K$ is equal to the internal energy of $n_{2}$ moles of helium at temperature $300\ K$. The ratio of $n_{1}/n_{2}$ is

Question 14 :
The total kinetic energy of translatory motion of all molecules of 5 litres of nitrogen exerting a pressure is 3000J

Question 15 :
<p class="wysiwyg-text-align-left">Three containers of the same volume contain&#160;three gases. The masses of their molecules being&#160;m$_{1}$, m$_{2}$ and m$_{3}$ and number of molecules in these&#160;containers is N$_{1}$, N$_{2}$ and N$_{3}$. The pressure in the&#160;containers are P$_{1}$, P$_{2}$ and P$_{3}$ respectively. All the&#160;gases are now mixed up and put in these&#160;containers. The pressure P of the mixture is</p>

Question 16 :
A cylinder of capacity $20\:L$ is filled with $H_2$ gas. The total average kinetic energy of translatory motion of its molecules is $1.5\times 10^5\:J$. The pressure of hydrogen in the cylinder is

Question 17 :
One mole of an ideal monoatomic gas is mixed with 1 mole of an ideal diatomic gas. The molar specific heat of the mixture at constant volume is :

Question 18 :
Estimate the mean free path of a cosmic ray proton in the atmosphere at sea level. Given $\sigma = 10 ^{-26} cm^2$

Question 19 :
A gas mixture consists of 2moles of oxygen and 4moles of Ar at temperature T. Neglecting all vibrational modes, the total internal energy of the system is

Question 20 :
A gas has an average speed of $10 m/s$ and an average time of $0.1 s$ between collisions. What is its mean free path?<br/>

Question 21 :
One mole of an ideal gas $\left (C_{v,m}\, =\,&#160;\displaystyle \frac {5}{2} R \right )$&#160;at $300$ K and $5$ atm is expanded adiabatically to a final pressure of $2$ atm against a constant&#160;pressure of $2$ atm. Final temperature of the gas is:

Question 22 :
2 moles of an ideal gas A ($ {C}_{P} $ $= 4R$) and 4 moles of an ideal gas B ($ {C}_{V} $ $= \dfrac {3R}{2}$) are taken together in a&#160;container and allowed to expand reversibly and adiabatically from 49L to 64L, starting from an initial&#160;temperature of $ {47}^{0} $C. The final temperature of the gas is :

Question 23 :
A vessel contains air at a temperature of $15^{0}C$ and 60% R.H. What will be the R.H if it is heated to $20^{0}C$? (S.V.P at $15^{0}C$ is 12.67 &amp; at $20^{0}C$ is 17.36mm of Hg respectively)

Question 24 :
Let $\overline {v}, v_{rms}$ and $v_{p}$, respectively, denote the mean speed, root mean square speed and most probable speed of the molecules in an ideal monatiomc gas at absolute temperature $T$. The mass of a molecules is $m$. Then

Question 25 :
One half mole each of nitrogen, oxygen and carbon dioxide are mixed in enclosure of volume $5$ litres and temperature $27^o$C. The pressure exerted by mixture is $(R=8.31J mol^{-1}K^{-1})$

Question 26 :
Some gas at $300\ K$ is enclosed in a container. Now, the container is placed on a fast moving train. While the train is in motion, the temperature of the gas

Question 27 :
In a certain gas $\displaystyle \frac{2}{5}$th of the energy of molecules is associated with the rotation of molecules and the rest of it is associated with the motion of the centre of mass. The average translation energy of one such molecule, when the temperature is $27^{\circ}C$ is given by $x\times 10^{-23}\ J$,then find $x$?<br/>

Question 28 :
A certain mass of an ideal gas undergoes a reversible isothermal compression. Its molecules,&#160;compared with the initial state,&#160;will then have the same<br/>(i) root mean square velocity<br/>(ii) mean momentum<br/>(iii) mean kinetic energy<br/>

Question 29 :
Two&#160;blocks of the same metal having the same mass and at temperature $T_1$&#160; and $T_2$, respectively. are brought in contact with each other and allowed to attain thermal equilibrium at constant pressure. The change in entropy, $\Delta S$, for this process is :

Question 30 :
One mole of an ideal gas expands against a constant external pressure of 1 atm from a volume of $10d{ m }^{ 3 }$ to a volume of $30d{ m }^{ 3 }$. What would be the work done in joules?