Which of the following is true about the role of solids and

Which of the following is true about the role of solids and liquids in equilibrium processes

Question 4 options:

The concentration of a pure liquid will change with the addition of a solute.

The concentration of a solid or a pure liquid is constant and not included in the equilibrium expression as long as some of the pure substance is present.

The concentration of a pure liquid must be included in the equilibrium constant expression.

The concentration of a solid increases as a solid is precipitated out of solution.

Solution

pure substance are not included in Kc expression
This is because there concentration can be assumed constant as they are pure

So, answer should be 2nd option

Answer:
The concentration of a solid or a pure liquid is constant and not included in the equilibrium expression as long as some of the pure substance is present.