Water

Question 1

State two uses of water to the industry and homes each

Answer 1

To the industry:

• As a coolant to reduce the temperature of some industrial processes e.g: in nuclear power plants
• Watering crops

To homes:

• Drinking, cooking and washing
• General sanitation.

Question 2

State two natural sources of water

Answer 2

Sea water, Ground Water (Boreholes), Rivers, Reservoir, Dam, Streams, etc

Question 3

Describe one chemical test for water

Answer 3

Test: Add the sample to anhydrous Copper (II) Sulphate
Result: The anydrous copper(II) Sulphate turns from white to blue

Test: Add the sample to anhydrous Cobalt(II) Chloride
Result: The anydrous cobalt(II) Chloride turns from blue to pink

Question 4

Describe one chemical test for PURE water

Answer 4

Test: Measure the boiling point of the water or the melting point of ice
Result: Boiling point is 100oC, Melting point is 0oC
[If the water is impure, b.p, would be higher than 100oC, and m.p. would be lower than 0oC]

Question 5

Explain why distilled water is preferred for chemical analysis

Answer 5

The chemical substances in tab water will interfere with the results of the chemical analysis

Question 6

Describe the process of water treatment

Answer 6

Water is pumped from a water source, such as a lake, river, or groundwater, into the water purification plant via a pump station. After water is pumped into the treatment plant, the purification process begins. Coagulant chemicals are added to the water and mixed at a high rate. Following the coagulation process, the water and floc particles are sent into a sedimentation basin. The filtration process allows water to pass through natural filters of variable sizes and compositions. To protect against bacteria, viruses, and other microbes, the water must be disinfected. In most cases, this is done using chemicals such as chlorine or with ultraviolet light.After the water purification process has been completed, the water is pumped into water storage tanks.

Question 7

What is chlorination?

Answer 7

water chlorination is the process of adding chlorine or chlorine compounds such as sodium hypochlorite to water. This method is used to kill bacteria, viruses and other microbes in water.

Question 8

State two advantages of substances in natural water

Answer 8

• dissolved oxygen for aquatic life

- some metal compounds provide essential minerals for life