A student was comparing the solubility of equal amounts of table salt and table sugar at different temperatures. The table below shows the four samples that the student used and the temperature of the water that they were dissolved in. Which of the samples most likely had the highest solubility?

Chemical formula

Temperature of water (°C)

1

Table sugar

C12H22O11

80

2

Table sugar

C12H22O11

45

3

Table salt

NaCl

55

4

Table salt

NaCl

63

First, we distinguish whether table sugar or table salt will be more soluble. The bonds between the molecules of the table sugar are weaker than the bonds between the molecules of salt. Therefore, it is easier for the sugar molecules to dissolve.

Next, we evaluate the effect of temperature on solubility. As the temperature of a solvent increases, it is able to hold more and more solute. This means that the sample with table sugar kept at the highest temperature will contain the most dissolved solute, and this is sample 1.