How do I solve a heat of reaction problem similar to this one?

Question

18. For which one of the following reactions is the heat of the reaction also a heat of formation of the product?
a) N2(g) + 3H2(g) ----> 2NH3(g)
b) (1/2)N2(g) + O2(g) ----> NO2(g)
c) 6C(s) + 6H(g) ----> C6H6(l)
d) P(g) + 4H(g) + Br(g) ----> PH4Br(l)
e) 12C(g) + 11H2(g) + 11O(g) ----> C6H22O11(s)

Answer 1

Since heat of reaction is equal to the difference between the heats of formation of products and the heats of formation of the reactants, and knowing that heats of formation of elements (such as N2, H2, O2, C, P, etc.) are zero, you should be able to figure out which one has ∆H_reaction = ∆H_formation of products.  If not, submit the question again, showing how you've tried to figure it out, and more help will be on the way.