$word_{count}$: 180

$delta_H$(T2) = $delta_H$(T1) + $delta_{Cp}$(T2 - T1). $delta_{Cp}$ = sum(Cp products) - sum(Cp reactants). This relates reaction enthalpy at different temperatures. Similarly: $delta_U$(T2) = $delta_U$(T1) + $delta_{Cv}$(T2 - T1). Physical meaning: if $delta_{Cp}$ > 0 (products have higher heat capacity), the reaction becomes more endothermic (or less exothermic) with increasing temperature. If $delta_{Cp}$ < 0, the reaction becomes more exothermic with increasing temperature. If $delta_{Cp}$ = 0, enthalpy is temperature-independent. Application: calculating $delta_H$ at non-standard temperatures when standard data is given at 298 K. The equation assumes Cp is constant over the temperature range (valid for small $delta_T$). For large ranges, integration with Cp as a function of T is needed (rarely required for JEE). Also applies to entropy: $delta_S$(T2) = $delta_S$(T1) + $delta_{Cp}$ ln$\frac{T2}{T1}$.