Environmental chemistry: water

Hard water contains dissolved salts of:

• 1 Calcium and magnesium
• 2 Sodium
• 3 Hydrogen
• 4 Potassium only

Temporary hardness is removed by:

• 1 Filtering
• 2 Freezing
• 3 Boiling
• 4 Adding salt

Which of these is a water pollutant?

• 1 Nitrogen
• 2 Sewage
• 3 Hydrogen
• 4 Oxygen

Chlorine is added to drinking water to:

• 1 Make it hard
• 2 Add taste only
• 3 Add colour
• 4 Kill germs

Soap does not lather easily in:

• 1 Distilled water
• 2 Soft water
• 3 Rain water
• 4 Hard water

Water is a good solvent because it is:

• 1 Polar
• 2 Non polar
• 3 A metal
• 4 A gas

The process of removing salt from sea water is:

• 1 Desalination
• 2 Evaporation only
• 3 Sedimentation
• 4 Filtration

Ion exchange can be used to:

• 1 Soften hard water
• 2 Make water hard
• 3 Add oxygen
• 4 Add colour

Waterborne diseases such as cholera are caused by:

• 1 Sunlight
• 2 Contaminated water
• 3 Pure water
• 4 Cold weather