Molar Heat Capacity at Constant Volume (Cv = (ΔQ/ΔT)v = ΔU/ΔT)

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Cv = (ΔQ/ΔT)v = ΔU/ΔT

What each symbol means

SymbolWhat it stands for
CvMolar heat capacity at constant volume (J mol⁻¹ K⁻¹)
ΔQHeat supplied at constant volume (J)
ΔTTemperature change (K)
ΔUChange in internal energy (J)

When to use this

Per mole of ideal gas. For n moles: Q = nCvΔT at constant volume, ΔU = nCvΔT for any process. At constant volume ΔV = 0, so no work done — all heat goes into internal energy. U depends only on T for ideal gas.