Q 11-11-043JEE MainJEE Main 2026 (2 Apr, Shift 2)Easy
$5$ moles of unknown gas is heated at constant volume from $10^\circ$C to $20^\circ$C. The molar specific heat of this gas at constant pressure $c_p=8$ cal/mol.°C and $R=8.36$ J/mol.°C. The change in the internal energy of the gas is ______ calorie.
Numerical value type. Enter your answer.
Answer: 300
Convert $R$ to calories: $R=\dfrac{8.36}{4.18}=2$ cal/mol °C.
$c_v=c_p-R=8-2=6$ cal/mol °C.
$$\Delta U=nc_v\Delta T=5\times6\times10=300\ \text{cal}$$
Solution by Sreeraj P, M.Sc Physics