Answer:
- 65 kJ
Explanation:
Hess's Law of Constant Heat Summation (or just Hess's Law) states that regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes
A+2B + B + 2C ===> C +D + 2C+ D
-20kJ -45 kJ ===> 3C + 2D
-65 kJ
