Answer: The Hrxn for the reaction C(s) + O2(g) -> CO2(g) is the same as the Hf for CO2(g).
The Hf for Br2(l) is 0 kJ/mol by definition
The Hrxn for the reaction 1.5H2(g) + 0.5N2(g) -> NH3(g) is the same as the Hf for NH3(g).
Step-by-step explanation: