Question

Using Table 9.4, calculate an approximate enthalpy (in kJ) for the reaction of 1.02 g gaseous methanol (CH3OH) in excess molecular oxygen to form gaseous carbon dioxide and gaseous water.

Answer 1

What's Table 9.4?
2CH3OH(g)+ 3O2(g) ==> 2CO2(g) + 4H2O(g)

Look in you text/notes and find delta H formation.
dHrxn = (n*dHformation products) - (m*dHformation reactants) = some number which I'll call z.

Then z x (1.2/2*molar mass CH3OH)