Question

What is the heating value of 10 Kg of coal with heat of combustion 10 J/Kg?

(a) -10 J

(b) 10 J

(c) -100 J

(d) 100 J

This question was posed to me in an interview.

I want to ask this question from Heat of Combustion topic in chapter Application of Energy Balances in the Absence of Chemical Reactions and Energy Balances: How to Account for Chemical Reaction of Basic Chemical Engineering

Answer 1

Correct choice is (c) -100 J

For explanation I would say: Heating value = – Heat of combustion = -10*10 = -100 J.