Solubility

Question 1

Define solvent

Answer 1

A substance that does the dissolving

Question 2

Define solute

Answer 2

A substance that is dissolved

Question 3

Solution definition

Answer 3

A substance dissolved in a solvent, a mixture of a solute and a solvent

Question 4

Saturated solution definition

Answer 4

A solution which cannot dissolve any more solute

Question 5

Solubility

Answer 5

The maximum mass of solid which will dissolve in 100g of water at a given temperature

Question 6

Equation for solubility

Answer 6

Mass of solute
—————— x 100
Mass of solvent

Question 7

Name four factors affecting solubility

Answer 7

• temperature
• stirring
• volume of solvent
• mass of solute

Question 8

When a fish is caught in a river and put into a jar of water, it survives for a long time if the jar is kept cool. However, if the water in the jar is allowed to warm up, the fish soon dies. Explain why this happens

Answer 8

• The fish requires oxygen to survive.
• The solubility of the oxygen in the water decreases as the temperature of the water increases. - Therefore, there is less oxygen available for the fish as the jar is warmed up

Question 9

Explain the effect of temperature on the solubility of solids

Answer 9

Solubility increases with temperature

Question 10

Explain the effect of temperature on the solubility of gasses

Answer 10

Solubility decreases in gases with higher temperatures

Question 11

What is the effect of solubility of gases at higher temperatures concerning global warming?

Answer 11

CO2 is less soluble, resulting in an increase of gaseous CO2 in the atmosphere

Question 12

Why is a glass rod used to stir saturated solutions ?

Answer 12

Spatulas used for stirring may contaminate other chemicals, and sometimes a metal spatula may react with a solution