Air and Water

Question 1

Cobalt(II)Chloride turns…

Answer 1

blue to pink in the presence of water

Question 2

Anhydrous Copper(II)sulfate turns…

Answer 2

white to blue in the presence of water

Question 3

Water treatment:

Answer 3

• screen (traps twigs and paper)
• sedimentation tank
• fine filter (removal of organic waste)
• chlorination
• storage tank

Question 4

Industrial uses of water:

Answer 4

• Coolant
• as a Solvent
• in the production of ethanol

Question 5

Home uses of water:

Answer 5

• drinking
• cooking
• sanitation

Question 6

What is the composition of air?

Answer 6

Nitrogen: 78%
Oxygen: 21%
Other gases: 0.94%

Question 7

What is Carbon Monoxide?

Answer 7

Toxic gas, made from incomplete combustion

Question 8

what is Sulfur Dioxide?

Answer 8

forms Acid rain, made from incomplete combustion

Question 9

What are the problems with acid rain?

Answer 9

• corrosion of metal structures
• pollutes crops
• creates an acidic pH in lakes
• damage to aquatic organisms

Question 10

What are Oxides of Nitrogen?

Answer 10

• causes in car exhausts

- forms acid rain

Question 11

what are Lead compounds

Answer 11

• old water pipes, old engines, petrol

- damages central nervous system

Question 12

How does Iron rust?

Answer 12

when in contact with Oxygen and water, forming hydrated Iron(III)oxide

Question 13

Barrier methods to prevent rusting:

Answer 13

Paint, oil, grease, plastic

Question 14

Galvanising is…

Answer 14

a process where the iron to be protected is coated with a layer of zinc