If you need to multiply the following reaction by 2 to be an intermediate reaction in a Hess's law problem, what would be the final value for the enthalpy of reaction you use for this intermediate reaction? C2H4 + 3 O2 2 CO2 + 2 H2O, H = -1410 kJ
5 answers
It works this way. If you multiply the equation you use the same multiplier for dH. If you reverse the equation, change the sign of dH. If you reverse the equation AND multiply it, then multiply by the same multiplier and change the sign.
2820 kj
-2820 kj
The answers -2820 kj (APEX)
1410kJ (Apex)