Given equation (1) with ΔH = -1560 kJ and equation (2) with ΔH = -283 kJ, find ΔH for the reaction (1) - (2).
Answer and explanation
Correct answer: D. -1277 kJ
- Step 1: Subtracting equations subtracts their enthalpy changes.
- Step 2: ΔH = -1560 - (-283) = -1277 kJ.
Answer
-1277 kJ.
Why not the others: -1843 kJ, 1277 kJ and -1560 kJ do not fit.
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