Finding heat formation!

using the reaction:
C6H12O6(s) + 6O2 ==> 6CO2(g) + 6H2O(l) + 674.6 kcal
find the heat of formation for glucose, C6H12O6

Well, the heat change for a reaction (-674.6 kcal) is equal to the heat of formation of the products minus the heat of formation of the reactants. In equation form,

-674.6 kcal = 6(heat of formation of CO2) + 6(heat of formation of H2O) - heat of formation of glucose.

So, you can look up those values in your text and use this equation to calculate the heat of formation of glucose.