Question

If the ratio of the specific heats of steam is 1.33$=$ and R$=$8312J/kmole K. Find the molar heat capacities of steam at constant pressure and constant volume.

• A. $33.5kJ/kmole$ , $25.19kJ/kgK$
• B. $25.19kJ/kmole$ , $33.5kJ/kgK$
• C. $18.82kJ/kmole$ , $10.82kJ/Kmole$
• D. $24.12kJ/kmole$ , $16.12kJ/Kmole$

Answer 1

Answer: (B)

$25.19kJ/kmole$ , $33.5kJ/kgK$

$\text{Given:-}$Ratio of the specific heats $=1.33$

$R=8312J/kmolek$

$\text{Solution:-}$

We know that,

$\gamma =\frac{C_P}{C_V}=1.33$

$R=8.312J/kmoleK$

Now,

$C_P=\frac{\gamma R}{\gamma -1}$

$=\frac{1.33\times 8.312}{1.33-1}$

$=\frac{11054.96}{0.33}$

$C_P=33.50kJ/kmoleK$

$Similarly,$

$C_V=\frac{R}{\gamma -1}$

$C_V=25.187kJ/kmoleK$

.

$\text{Hence the correct option is B}$