Do any liquids not evaporate?

Do All Liquids Evaporate?

When we think of liquids, we usually picture water disappearing from a puddle or rubbing alcohol vanishing off our skin. This everyday process, known as evaporation, occurs when individual molecules gain enough thermal energy to break free from their neighbors and escape into the air as vapor. However, if you leave a bowl of olive oil on the kitchen counter, it appears to sit there indefinitely without losing a drop. This leaves many wondering whether certain liquids simply refuse to evaporate.

Strictly speaking, virtually all liquids possess some degree of vapor pressure, but many do not evaporate in any visible or practical timeframe at room temperature. The reason comes down to molecular energy distribution. In substances like cooking oil or liquid mercury, the forces holding the molecules together are strong, and the random collisions between them rarely pass enough energy to a single molecule for it to break away.

Because these molecules fail to concentrate heat energy effectively, the shift into a vapor state is extraordinarily rare. So, while thermodynamic principles suggest that almost every liquid loses an imperceptible fraction of its mass over immense stretches of time, for all practical human purposes, some liquids effectively never evaporate under normal conditions.