Practice question

**Internal energy change** ΔU = Q - W, for same initial and final states ΔU same regardless of path, but Q and W differ, e.g., isothermal expansion from V₁ to V₂ ΔU=0 Q=W=n R T ln(V₂/V₁), adiabatic expansion between same volumes ΔU=-W, Q=0, different Q,W same ΔU if same T change, illustrating state vs path functions. Δ U = μ C_v Δ T . μ = 0.8 , C_v = 20.8 , Δ T = 370 - 310 = 60 . Δ U = 0.8 × 20.8 × 60 = 998.4 J ≈ 998 J . Using first law ΔU = Q - W, W