How much heat is released when 2 mol of a substance burns, if the enthalpy of combustion is -300 kJ/mol?
Answer and explanation
Correct answer: C. 600 kJ
- Step 1: Heat = moles x molar enthalpy change in magnitude. Step 2. = 2 x 300 = 600 kJ. Answer: 600 kJ. Why not the others: 150 kJ: That divides by 2. 300 kJ: That is for one mole. -300 kJ: That is the molar enthalpy, not the heat for 2 mol.
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