State Hess's law of constant heat summation. (ii) Give an example for an extensive property.

Question

(a) (i) State Hess's law of constant heat summation. 

(ii) Give an example for an extensive property.

(b) Explain Born-Haber cycle for the formation of 1 mole of sodium chloride crystal.

Answer 1

(a) (i) Correct Statement 

(ii) Mass, Volume, I.E, Enthalpy, heat capacity.

Detailed Answer :

(a) Hess's law states that the amount of heat evolved or absorbed in a chemical reaction is same whether the reaction takes place in one step or a number of steps.