A frictionless piston filled with 0.04 mol of an ideal gas expands isothermally from 50 mL to 375 mL — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

Because the process is maintained at a constant temperature, it is an isothermal process. For an ideal gas, internal energy depends only on temperature, so $\Delta U = 0$. By the First Law ($\Delta U = q + w$), $0 = 208 + w \Rightarrow w = -208 \text{ J}$.