Five moles of an ideal gas is expanded isothermally from to at 300 K. Which of the following is inco — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

During an isothermal expansion of an ideal gas, $\Delta U = 0$ (so B is correct). The gas does work of expansion ($w < 0$), so to keep $\Delta U = 0$, it must absorb an equivalent amount of heat ($q = -w > 0$). Therefore, the statement that no heat is absorbed is incorrect.