Question

Hi, I have a lab question and I'm kind of confused on how to approach it.

Evaluation of molar enthalpy of dissociation of formic acid, deltaHdiss.

Given:
H1 = -58010 J/mol; H2 = -59758.4J/mol

They tell use to use Hess's Law to determine the enthalpy of dissociation

Thanks!

Answer 1

Hess' Law uses manipulation of the equations used to form the correct equation in total.

1. H3O+ + OH- > 2H2O H1= -58010 J/mol
2. HCOOH + OH- > H2O + HCOO- H2 = -59758 J/mol

2. HCOOH + OH- > H2O + HCOO- H2 = -59758 J/mol
1. [x-1] = 2H2O > OH + H3O H1 = 580101 J/mol
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HCOOH + H2O > H3O + HCOO H= -1748 J/mol