Question

The specific volume of a gas is 5 m^3/Kg, at 25 Pa, H = 40 J/Kg and at 40 Pa, H = 90 J/Kg, what is the heat transferred to the system?

(a) -5 J/Kg

(b) 5 J/Kg

(c) -25 J/Kg

(d) 25 J/Kg

This question was posed to me by my school principal while I was bunking the class.

I would like to ask this question from Application of the Energy Balance to Closed Systems 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

The correct option is (c) -25 J/Kg

Explanation: Q = ∆H – V∆P = (90 – 40) – 5(40 – 25) = -25 J/Kg.