Carbon dioxide is being used as an environmentally safe liquid solvent for reactions. If the reaction is run at a temperature of 15^oC, what must the minimum pressure of the reaction vessel be? The phase diagram for carbon dioxide is shown below.

Question

Quizplus · Accepted Answer

At a temperature of 15°C, the minimum pressure required for carbon dioxide to exist in a liquid state is about 5 atm (according to the phase diagram). However, in order to use carbon dioxide as a solvent for reactions, it is necessary to increase the pressure above the vapor pressure of CO2 at that temperature. Therefore, the minimum pressure required for the reaction vessel would be about 100 atm, which is well above the vapor pressure of CO2 at 15°C. Choice C is the closest option to this value, making it the best answer.

Carbon Dioxide Is Being Used as an Environmentally Safe Liquid