Distillation is a process of separating a liquid from solutes or other liquids. It utilizes the boiling point differences to separate substances. A substance with a low boiling point will evaporate first in a distillation column and will be isolated first. The question is asking which solution will be isolated first; therefore, we need to figure out which solution has the lowest boiling point. Recall that the boiling point of a solution is elevated when there are more solutes present in the solution. Sodium chloride () contributes two solutes (sodium ions and chloride ions). Calcium nitrate () contributes three solutes (one calcium ion and two nitrate ions). Sucrose does not dissociate into ions in solution; therefore, it only contributes one solute. This means that the sucrose solution will have the lowest amount of molecules in solution, the lowest boiling point, and will be separated first.

There are two types of distillation. Simple distillation is used to separate molecules that have very different boiling points. Fractional distillation is used to separate molecules with small differences in boiling points. Fractional distillation is often used if the difference between boiling points is less than . In simple distillation, the vapor is immediately collected in a condenser. On the other hand, fractional distillation allows vapor to condense and revaporize several times. These repeated cycles allow fractional distillation to purify the vapor better than simple distillation.

Distillation is used to separate molecules with different boiling points. Simple distillation is used to separate molecules with vastly different boiling points. Fractional distillation, on the other hand, is a refined form of simple distillation that can be used to separate molecules with similar boiling points. Note that fractional distillation can separate molecules with either different or similar boiling points; therefore, fractional distillation can be used to separate any of the given mixtures. 

Rate of distillation is increased when the ability of a substance to become a vapor is increased. Recall that vapor is created when enough heat is applied to the liquid. The temperature at which the liquid becomes vapor is called the boiling point. A liquid turns into a vapor when the vapor pressure (pressure applied by the vapor from the liquid) equals the atmospheric pressure. Decreasing the atmospheric pressure will make it easier for the liquid to turn into a vapor; therefore, this will increase the rate of distillation.

Decreasing the vapor pressure will remove vapor from system. This will make it harder to distill substances. Decreasing temperature will move the system away from the boiling point, thereby decreasing the amount of vapor. Decreasing mole fraction of the substance will decrease the surface area of the substance (at the surface of the solution). Liquid molecules need to be present at the surface to escape the solution and become vapor; therefore, decreasing mole fraction will decrease the amount of vapor.