Which of the following statements is true for an ideal solution?
The enthalpy of mixing is zero.
The volume of the solution is equal to the sum of the volumes of the components.
The entropy of mixing is positive.
The activity coefficient is greater than 1.
In an ideal solution, the enthalpy of mixing is zero, which means that no heat is evolved or absorbed during the mixing process. The other statements are false. The volume of the solution is not necessarily equal to the sum of the volumes of the components, the entropy of mixing can be positive or negative depending on the nature of the components, and the activity coefficient is always equal to 1 in an ideal solution.