A phase change for carbon dioxide that occurs spontaneously at 20.°C and 1.0 atmosphere is represented by the balanced equation below. CO2(s) + energy ==>CO2(g)

Write the name of this phase change.

The name of the phase change is;

Sublimation.

Explanation:

CO₂(s) + energy ⇒ CO₂(g)

Sublimation is the transition of a substance from its solid state to the gaseous state without first turning to a liquid due the high rate of absorption of of thermal energy of the substance such that the substance does not melt first.

As such sublimation is the endothermic process taking place at  a temperature and pressure lower than the triple point of the substance in the substance's phase diagram. The triple point is the lowest temperature and pressure at which a substance can exist as a liquid.