CHANGE OF STATE CONDENSATION GAS TO LIQUID Condensation

CHANGE OF STATE

CONDENSATION GAS TO LIQUID • Condensation is the change in state from a gas to a liquid. • The temperature at which condensation occurs is the condensation point. • Condensation and vaporization are the opposite of each other. Consequently they occur at the same temperature. • If energy is being added, vaporization occurs. If energy is removed, condensation occurs. • Condensation is exothermic (energy is removed).

SUBLIMATION: SOLID TO GAS • Sublimation is the change in state that occurs when a solid changes directly into a gas. Example: dry ice • Sublimation is an endothermic change. • Energy must be added for the solid’s particles to overcome their attraction

DEPOSITION: GAS TO SOLID • Deposition is the opposite of sublimation. • With deposition, a gas changes directly to a solid without going through the liquid phase. • Energy is released when deposition occurs so it is an exothermic process.

CHANGE OF TEMPERATURE VS CHANGE OF STATE • When substances lose or gain energy, one of two things will happen: – Temperature changes OR (NOT BOTH) – State changes • The temperature of a substance does not change until the change in state is complete. Example: The temperature of boiling water stays at 100○C until it has all evaporated.