1. Which of the following formulae is wrong
a) \[C_{V}=\frac{R}{\gamma-1}\]
b) \[C_{P}=\frac{\gamma R}{\gamma-1}\]
c) \[C_{P}\diagup C_{V}=\gamma\]
d) \[C_{P}- C_{V}=2R\]
Explanation: This formula is wrong -> \[C_{P}- C_{V}=2R\]
2. For hydrogen gas \[C_{P}- C_{V}=a\] and for oxygen gas \[C_{P}- C_{V}=b\] . So the relation between a and b is given by
a) \[a =16b\]
b) \[b =16a\]
c) \[a =4b\]
d) \[a =b\]
Explanation: \[a =b\]
3. For a gas the difference between the two specific heats is 4150 J/kg K. What is the specific heats at constant volume of gas if the ratio of specific heat
is 1.4
a) 8475 J / kg K
b) 5186 J / kg K
c) 1660 J / kg K
d) 10375 J / kg K
Explanation:
4. The quantity of heat required to raise one mole through one degree Kelvin for a monoatomic gas at constant volume is
a) \[\frac{3}{2}R\]
b) \[\frac{5}{2}R\]
c) \[\frac{7}{2}R\]
d) 4 R
Explanation: The quantity of heat required to raise one mole through one degree Kelvin for a monoatomic gas at constant volume is \[\frac{3}{2}R\]
5. The specific heat relation for ideal gas is
a) \[C_{P}+ C_{V}=R\]
b) \[C_{P}- C_{V}=R\]
c) \[C_{P}\diagup C_{V}=R\]
d) \[C_{V}\diagup C_{P}=R\]
Explanation: The specific heat relation for ideal gas is \[C_{P}- C_{V}=R\]
6. The specific heat of 1 mole of an ideal gas at constant pressure \[\left(C_{P}\right)\] and at constant volume \[\left(C_{V}\right)\] which is correct
a) \[C_{P}\] of hydrogen gas is \[\frac{5}{2}R\]
b) \[C_{V}\] of hydrogen gas is \[\frac{7}{2}R\]
c) \[H_{2}\] has very small values of \[C_{P}\] and \[C_{v}\]
d) \[C_{P} - C_{v}\] = 1.99 cal/mole-K for \[H_{2}\]
Explanation: \[C_{P} - C_{v}\] = 1.99 cal/mole-K for \[H_{2}\]
7. What is the ratio of specific heats of constant pressure and constant volume for \[NH_{3}\]
a) 1.33
b) 1.44
c) 1.28
d) 1.67
Explanation: Ratio of specific heats of constant pressure and constant volume for \[NH_{3}\] is 1.33
8. If two moles of diatomic gas and one mole of mono atomic gas are mixed then the ratio of specific heats is
a) \[\frac{7}{3}\]
b) \[\frac{5}{4}\]
c) \[\frac{19}{13}\]
d) \[\frac{15}{19}\]
Explanation: If two moles of diatomic gas and one mole of mono atomic gas are mixed then the ratio of specific heats is \[\frac{19}{13}\]
9. One mole of ideal monoatomic gas \[\left(\gamma=5\diagup3\right)\] is mixed with one mole of diatomic gas \[\left(\gamma=7\diagup5\right)\] . What is \[\gamma\] for the mixture? \[\gamma\] denotes the ratio of
specific heat at constant pressure, to that at constant volume
a) 3/2
b) 23/15
c) 35/23
d) 4/3
Explanation:
10. A gaseous mixture contains equal number of hydrogen and nitrogen molecules. Specific heat measurements on this mixture at temperatures
below 100 K would indicate that the value of \[\gamma\] (ratio of specific heats) for this mixture is
a) 3/2
b) 4/3
c) 5/3
d) 7/5
Explanation: 5/3