Fact 1: Heating salt water causes the water to evaporate while the salt remains.

Fact 2: Evaporation of the water leaves the salt on the surface.

Given the two facts above, answer the question "heating salt water leaves the salt where?" with the following options: 
- solid, liquid, gas
 - on the surface
 - Solutions
 - epidermis and dermis
 - lowered energy cost
 - energy barrier
 - an object
 - near the shoreline


 

  on the surface       