Question

What is the vapor pressure of ammonia at 305 K, if it is given that the vapor pressure of ammonia at 315 K is 5 mm Hg and at 325 K it is 6 mm Hg?

(a) 1 mm Hg

(b) 2 mm Hg

(c) 3 mm Hg

(d) 4 mm Hg

The question was posed to me during a job interview.

I would like to ask this question from Modeling and Predicting Vapor Pressure in portion Real Gases: Equations of State, Single Component Two Phase Systems, Saturation & Condensation of Basic Chemical Engineering

Answer 1

Correct answer is (d) 4 mm Hg

Explanation: p305K = 5 – (315 – 305)*(6 – 5)/(325 – 315) = 5 – 1 = 4 mm Hg.