The compressibility factor for H₂ and He is usually:

1. >1                                     

2. =1

3. <1                                     

4. either of these

The compressibility factor of an ideal gas is:

1. zero                         

2. infinite

3. 1                               

4. -1

The compressibility of a gas is less than unity at STP. Therefore:

1. V_m > 22.4 litre                           

2. V_m < 22.4 litre

3. V_m = 22.4 litre                           

4. V_m = 44.8 litre

At high pressure, the compressibility factor 'Z' is equal to- 

1. Unity

2. 1-$\frac{\mathrm{Pb}}{\mathrm{RT}}$

3. 1+$\frac{\mathrm{Pb}}{\mathrm{RT}}$

4. Zero

The compressibility factor for a real gas at high pressure is:-

1. 1

2. 1+Pb/RT

3. 1-Pb/RT

4. 1-RT/Pb

A gas at 350 K and 15 bar has a molar volume 20 percent smaller than that for an ideal gas under the same conditions. The correct option about the gas and its compressibility factor (Z) is:

Consider the following statements. If the van der Waals' parameters of two gases are given as

$\mathrm{a}/{\mathrm{dm}}^6 \mathrm{bar} {\mathrm{mol}}^{-2} \mathrm{b}/{\mathrm{dm}}^3 {\mathrm{mol}}^{-1}$
$\mathrm{Gas} \mathrm{A} 6.5 0.055$
$\mathrm{Gas} \mathrm{B} 2 0.01$

then:

1.  Critical volume of A > Critical volume of B
2.  Critical pressure A > Critical temperature of B
3.  Critical temperature of A > Critical temperature of B

Which of the above statement is incorrect?

1.  1 alone

2.  1 and 2

3.  1, 2 and 3

4.  2 and 3

 The van der Waals parameters for gases W, X, Y and Z are

Which one of these gases has the highest critical temperature?

1.  W

2.  X

3.  Y

4.  Z

The excluded volume of a gas will be larger, if $\frac{{\mathrm{T}}_{\mathrm{C}}}{{\mathrm{P}}_{\mathrm{C}}}$ is:

1.  small

2.  large

3.  equal to 1

4.  less than unity