Calculate the heat of reaction for the incomplete combustion of 67.0g propane producing carbon monoxide gas and water vapour.

Question

how would I go about and do this question?

What are you studying? Do you know how to use the thermodynamic tables (delta H^o, etc).
delta H^rxn = delta H_(products) - delta H_(reactants)

yes I do!

Look in the tables and find delta H for the products, subtract them from delta H for the the raactants and you will have delta H for the reaction.
You need to write a balanced equation first.
C3H8(g) + O2(g) ==> CO(g) + H2O(g)

Delta H(reaction) will be in kJ/mol and you will compare that with 67 g propane (converted to mols, of course).