Question

1 mole of $N{H}_3$ gas at ${27}^{\circ }C$ is expanded under adiabatic condition to make volume 8 times $(\upsilon =1.33)$. Final temperature and work done, respectively are:

• A. $150K,900cal$
• B. $150K,400cal$
• C. $250K,1000cal$
• D. $200K,800cal$

Answer 1

The correct option is A $150K,900cal$

As we know,

$T_2=T_1{\left(\begin{array}{c}\frac{V_1}{V_2}\end{array}\right)}^{{\rm Y}-1}$

$=150K$

$w=-C_V\Delta T$

$=-C_V(T_2-T_1)$

$=-3\times 2\times (150-300)$

$=900cal$