Question

Two moles of a monoatomic ideal gas is confined in a container and is heated such that its temperature increases by ${10}^{o}C$. The approximate change in its internal energy is ($R=8.31J/mole-K$)

• A. $+250$ joules
• B. $+350$ joules
• C. $-250$ joules
• D. $+450$ joules

Answer 1

The correct option is A $+250$ joules

Total translational kinetic energy

$=\frac{3}{2}nRT=\frac{3}{2}PV$

$\Delta E=n\frac{3}{2}R\Delta T$
$=2\times \frac{3}{2}\times 8.31\times 10=250J$