Why does salt water evaporate slower than fresh water?

The specific heat capacity of water is about 4.18kJ/kg*K while the specific heat of seawater is about 3.95kJ/kg*K

Specific heat capacity is a measure of heat required to increase temperature of something by Celsius or Kelvin.

Since water's heat capacity is great than that of seawater, then it takes more heat to bring its temperature up