Question

A diatomic gas is heated at constant pressure. If 105 J of heat is given to the gas, find the change in internal energy of the gas.

• A. 30 J
• B. 35 J
• C. 55 J
• D. 75 J

Answer 1

The correct option is D

75 J

$\Delta Q=\Delta U+\Delta W=\Delta U+nR\Delta T$

$\Delta Q=\Delta U(1+\frac{2}{f})$

For a diatomic gas, $f=5$

$\Delta U=75J$