The change in enthalpy refers to the amount of heat absorbed or heat evolved in a reaction which is carried out at constant pressure.
The change in enthalpy of a reaction is equal to the sum of formation of products minus sum of formation of reactants. It is denoted by [tex]\Delta H[/tex].
The given reaction is:
[tex]Zn + Cs_{2}SO_{4} \rightarrow 2Cs + ZnSO_{4}[/tex]
[tex]\Delta H = \Delta H_{f}^{0}(products))-\Delta H_{f}^{0}(reactants))[/tex]
Substitute the given values [tex]\Delta H_{f}^{0}[/tex](products) and [tex]\Delta H_{f}^{0}[/tex](reactants) in above formula, we get
[tex]\Delta H = -1,063 kJ -(-1,400 kJ)[/tex]
= [tex]+ 337 kJ[/tex]
Thus, change in enthalpy for the single replacement reaction is [tex]+ 337 kJ[/tex]
