Question

A gas expands from $100$ mL to $250$ mL at constant pressure of $2$ atm. Work done by the gas is?

• A. $5$ kJ
• B. $22$ J
• C. $30.4$ J
• D. $16$ J

Answer 1

Answer: (C)

$30.4$ J

According to the problem :-

Given that

$V_1=100ml$ and $V_2=250ml$

Pressure $P=2$ atm or $2\times 1.01\times {10}^{5}N{m}^{-2}$

Hence,

$W=\Delta PV$

Implies that

$(W=P(V_2-V_1)$

Putting all values in above equation, we have

$W=2\times 1.01\times {10}^5\left(0.250\times {10}^{-3}-0.100\times {10}^{-3}\right)$

Implies that

$=2\times 1.01\times {10}^5\times .15\times {10}^{-3}$

$=30.38$ joule