Correct Response: B. When salt is dissolved in water, it forms sodium (Na+) and chloride (Cl–) ions that become essentially surrounded by water molecules. While the volume of the water does not increase, the mass of the solution does, necessarily leading to an increase in density (mass per unit volume). While the crystal structure of the salt breaks down, this does not lead to a decrease in the distance between salt molecules (A). C is incorrect because adding salt to water tends to increase its surface tension and slow the evaporation rate. The chloride ions released from the salt do not combine with water molecules (D), nor is there a decrease in the mass of the salt crystals.
