Question

can someone explain Hess's law?

Answer 1

Hard to really get it without an example but...main definition is just

when given 2 chemical equations, the combined reaction of (heat) is the sum of each individual heat of reaction

Answer 2

actually i do have an example

N2(g)+2O2(g)>>>2NO2

Heat of reaction ^ 180 kj

2NO(g)+O2(g)>>>2NO2(g)

Heat of reaction ^ -112 KJ

heat of reaction is the sum...180+(-112)=68KH

Answer 3

*KJ

Answer 4

why did you subtract by 112

Answer 5

the heat of reaction of that equation was -112KJ, they will give you that

Answer 6

okay i think i get it thanks :)

Answer 7

Hess' law: the sum of the parts equals the whole.

Specifically to the energy change in reactions