(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Here's the formula I was given

CH4 (g) + 2O2 (g) >CO2(g) + 2H20 (l) : -803Kj

CH4 (g) + 2O2 (g) . CO2 (g) + 2H2O (g) : -891 Kj

Find enthalpy for vaporization of H2O

2. Relevant equations

3. The attempt at a solution

My soln

CO2(g) + 2H20 (l)>CH4 (g) + 2O2 (g) > : +803Kj

CH4 (g) + 2O2 (g)>CO2 (g) + 2H2O (g) : -891 Kj

Answer 88 Kj

BUT Book says:

1/2CO2(g) + 2H20 (l) > 1/2CH4 (g) + 2O2 (g) > : 1/2(+803Kj)

1/2CH4 (g) + 2O2 (g) > 1/2CO2 (g) + 2H2O (g) : 1/2(-891 Kj)

Answer 44Kj

Why would the balanced eqn have to be be balanced by halving CO2's and CH4's? I'm stumped

Any help would be great!

Thanks

Warren

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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