Question

Why water comes out when we add salt to salad?,

Answer 1

Because of the process of osmosis.

Answer 2

Water comes out when we add salt to salad is because salt increases the solute concentration and converts the outer environment into a hypertonic solution.  

In a hypertonic solution, when the solute concentration is more outside than inside the cell, water moves out from its region of ‘high concentration’ to its region of ‘low concentration’ to create an isotonic environment.  

Hence, when salt is added to salad, water is released out in response to a hypertonic environment.