Question

A gas occupies $2$ litre at STP. It is provided $300J$ heat so that its volume becomes $2.5$ litre at $1atm$ . Calculate change in internal energy.

• A. $249.5J$
• B. $121.6J$
• C. $351.8J$
• D. $163.4J$

Answer 1

Answer: (A)

$\boxed{\Delta E=q+w}$
$\Delta E=300-1\left(2.5-2\right)101.3$
$=300-0.5\times 101.3$
$\boxed{\Delta E=249.5J}$