In the given graph, pq, qr and st represent ?
We know that pure solvent has a higher freezing point in comparison to the solution at a given pressure.
Thus, in the graph pq represents the liquid state of solvent, qr represents solid solvent and st represents the liquid state of solution.
This will happen because of depression in freezing point because of the presence of solute particles present in the solution.
Thus the correct answer is B.