Sensible heat is the amount of heat, (molecular motion), you can measure with a thermometer. It’s the amount of heat you add or remove to a substance that changes a substance temperature but does not change the state of a substance.
Latent heat is heat added or removed that will change the state of a substance but does not affect the temperature of the substance. Water to steam is a change of state.
Example: We’ll look at a pot of water on a stove and see what happens. Using distilled water will give more accurate numbers
- The pot of water heats up from 40°F to 90°F. The water is getting nice and warm, but there’s no change of state (boiling/steam). So this is only sensible heat added
- As the pot of water continues to accept heat from the burners, the pot eventually reaches 212°F, the boiling point. There’s a change of state happening as the liquid water changes to steam. Even with heat still being applied to the pot of water, the pot will remain at 212°F. This heat energy being applied is the latent heat causing the change in state from liquid to vapor steam