derive an expresion for the effectof tempreture on heat of reaction at constant pressure?
 

Dear student,

The constant-pressure heat capacity tells us about hange in enthalpy of a system with rise in temperature at constant pressure.

$$\begin{gathered} To derive the relation, let us first look at \\ ∆H=∆U+p∆V; at const. pressure. \\ Because enthalpy is defined interms of state functions U, p \& V, so, H is also \\ a state function. \\ So, change in enthalpy of a system is defined as heat transferred to the system at \\ cons\tan t pressure: \\ ∆H=q \left(1\right) \\ From definition of heat capacity, we have \\ C=\raisebox{1ex}{$q$}\!\left/ \!\raisebox{-1ex}{$∆T \left(2\right)$}\right. \\ Therefore, \\ {C}_p=\frac{∆H}{∆T} \\ The suffix \text{'}p\text{'} denotes cons\tan t pressure. \end{gathered}$$
Regards
Arnab Bhattacharya