Question

what is hess's law and with example

Answer 1

This law gives the relationship between heat of reaction
Statement: this law states that the enthalpy change (del h) during a chemical reaction is same whether the reaction takes place in one step or several steps
Example : consider a hypothetical reaction
A➡️D
Let del h = enthalpy change when A is converted to D directly
Let del H1= enthalpy change when A➡️B
Let delH2= enthalpy change when B➡️C
Let delH3=enthalpy change when C➡️D
According to Hesse's law
delH= delH1 +delH2+delH3

Answer 2

Answer:

Hess’s law states that the standard reaction enthalpy is the sum of the standard enthalpies of the intermediate reactions into which the overall reaction can be divided, while each occurs at the same temperature.