Question

Study the graphs in Figure 6.33 and answer these questions. (see attached image)

1: Which solute is most soluble in water at:
a: 0°C
b: 80°C

2: Do different solutes have different solubilities in water at a particular temperature?​

Answer 1

Hey there :)

The highest solubility of a solute will be when it has the greatest quantity in g when dissolved in 100 g of water. So the solute that is most soluble in water, will have a higher g/100 g water.

1:

a: 0°C - Sucrose will be the solute that is most soluble in water.

b: 80 °C - Also Sucrose will be the most soluble in water.

2:

Yes, as we can see in the graph, sucrose, potassium nitrate, ammonium sulfate and sodium chloride have different solubilities between them and at different temperatures. For example, solubility at 0 °C:

sucrose: 180 g / 100 g of water

potassium nitrate: ~10 g/ 100 g of water

ammonium sulfate: 80 g/100 g water

sodium chloride: 30 g/ 100 g of water