Question

What is the humid volume of the system at 100oF with humidity 20%?

(a) 18.6 ft3/lb

(b) 22.4 ft3/lb

(c) 26.5 ft3/lb

(d) 29.4 ft3/lb

I had been asked this question in an interview.

This key question is from Humidity (Psychrometric) Chart topic in portion Humidity Charts & their Use, Analysis of the Degrees of Freedom in a Steady – State Process, Solving Material and Energy Balances Using Process and Unsteady State Material and Energy Balances of Basic Chemical Engineering

Answer 1

The correct option is (a) 18.6 ft3/lb

The best explanation: V = (0.73T + 336)(1/29 + H/18) = (0.73*100 + 336)(1/29 + 0.2/18) = 18.6 ft3/lb.