What You Need to Know

A solute dissolves in a solvent to form a solution; in water solutions, water is the solvent

Concentration can be expressed as grams per litre (g/L) or moles per litre (mol/L)

"Like dissolves like": polar solvents (water) dissolve polar/ionic solutes; non-polar solvents dissolve non-polar solutes

Saturated solutions contain the maximum dissolved solute at a given temperature

Key Vocabulary

The substance dissolved in a solution (e.g. salt in saltwater)

The substance in which the solute dissolves (e.g. water in saltwater)

The amount of solute dissolved per unit volume of solution

A solution that contains the maximum amount of dissolved solute at a given temperature

Select the correct answer for each question. Click "Check Answer" to see if you are right.

Question 1

25 g of salt is dissolved in 500 mL (0.5 L) of water. What is the concentration in g/L?

12.5 g/L 25 g/L 0.5 g/L 50 g/L

Question 2

You add more salt to a solution but it no longer dissolves and falls to the bottom. The solution is now:

Saturated Unsaturated Dilute Supersaturated

Question 3

Oil and water do not mix. Oil dissolves in hexane (a non-polar solvent). This illustrates:

That oil is acidic The principle "like dissolves like": non-polar solutes dissolve in non-polar solvents That water is too cold That hexane is a base