Suppose you had molecular oxygen (O2) chilled enough so that it was in liquid form. Which of the following best describes the phase changes that would occur as you heated the liquid oxygen to high temperature?

Question

A) It would vaporize (evaporate) into a gas, then the molecules would dissociate into individual oxygen atoms, then the atoms would become increasingly ionized as you continued to raise the temperature.
B) The liquid molecules would quickly dissociate into a liquid of individual oxygen atoms. These atoms would then vaporize (evaporate) into a gas, and then become ionized to make a plasma.
C) It would vaporize (evaporate) into a gas, then the molecules would lose electrons until no electrons were left, then the molecules would dissociate into individual oxygen nuclei.
D) The liquid oxygen first would solidify. The solid would then vaporize (sublimate) into a gas, which would then become a plasma as the molecules lost their electrons, until finally it consisted of bonded pairs of oxygen nuclei stripped bare of any electrons.

Answer 1

A) It would vaporize (evaporate) into a gas, then the molecules would dissociate into individual oxygen atoms, then the atoms would become increasingly ionized as you continued to raise the temperature.