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**1. Homework Statement**

The heat of combustion of graphite and that of CO is 394kJ/mol and 283 kJ/mol, respectively. When 12g of graphite is combusted incompletely, the same volume of CO and CO2 are generated. Calculate the heat of generated by this combustion. Choose the closet value.(kJ)

A.197 B.253 C.308 D.339 E.505 F.677

**2. Homework Equations**

The answer is B.253kJ

**3. The Attempt at a Solution**

My idea is:

##C+O2→CO\\

1 \qquad \qquad 1## and ##ΔH_1=-394kJ/mol##

##CO+O2→CO2\\

0,5 \qquad \qquad 0,5## and ##ΔH_2=-0,5.283 kJ/mol##

So ##ΔH=ΔH_1+ΔH_2=-535,5kJ/mol##

Where is my wrong?

Thanks for helping