Question

One mole of a monoatomic gas is heated at a constant pressure of 1 atm from 0 K to 100 K. If the gas constant R = 8.32 J mol${}^{-1}$ K${}^{-1}$, the change in internal energy of the gas is approximately

• A. 2.3 J
• B. 46 J
• C. 8.67 X 10³ J
• D. 1.25 X 10³ J

Answer 1

The correct option is D 1.25 X 10³ J

$dU=C_{V}dT=\left(\frac{3}{2}R\right)dT=\frac{3}{2}\times 8.32\times 100=1.25\times {10}^{3}J$