Question

What is the ideal pressure needed for the manufacture of liquid CO2?

(a) 1atm

(b) 1.66atm

(c) 4.5atm

(d) 5.1atm

I have been asked this question by my college professor while I was bunking the class.

Origin of the question is Synthetic Organic Chemical Industries in portion Synthetic Organic Chemical Industries of Chemical Technology

Answer 1

Right option is (d) 5.1atm

To explain: Liquid CO2 can be manufactured only if the pressure is above 5.1 atm since triple point of CO2 exists only at pressure of 5.1atm. Triple phase of a substance is temperature and pressure at which all three phases of the substance coexist.