## 8.117

$\Delta U=q+w$

Dahriel Aron 3A
Posts: 60
Joined: Fri Sep 25, 2015 3:00 am

### 8.117

In question 8.117 it states
One step in the production of hydrogen as a fuel is the
reaction of methane with water vapor:

CH4 + H2O --> CO2 + 3 H2   enthalpy= -318 kJ

What is the change in internal energy for the production of
1.00 mol H2?

In the solutions manual they multiply by 2/3 mol to find the change in mols and I was wondering why they do this

Chem_Mod
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### Re: 8.117

The equation is balanced, but if you count the moles of gas on the right side of the equation there are more than on the left. So more moles of gas are created, which would increase the volume of the gas, and allow it to do work.

They found change moles by first dividing the equation by 3, then adding moles products and subtracting the total moles reactants.