The internal energy of a gas is given by . It expands from 100 to against a constant pressure of . T — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

$\Delta V = 200 - 100 = 100\text{ cm}^3 = 100 \times 10^{-6}\text{ m}^3 = 10^{-4}\text{ m}^3$. Work done $W = -P_{\text{ext}} \Delta V = -(10^5)(10^{-4}) = -10\text{ J}$. Change in internal energy $\Delta U = 1.5 \Delta(PV) = 1.5 P \Delta V = 1.5 \times (10^5) \times 10^{-4} = 15\text{ J}$. By First Law, $q = \Delta U - W = 15 - (-10) = 25\text{ J}$. Format as 0025.