Air

Question 1

What is the atmosphere made of?

Answer 1

About 21% oxygen, about 78% oxygen, argon (0.93%), carbon dioxide (0.04%), varying amounts of vapour and trace amounts of other gases

Question 2

Name two major air pollutants, their sources and adverse effects

Answer 2

Carbon monoxide:- Sources- incomplete combustion of fossil fuels e.g: incomplete combustion of gasoline. Adverse effect- poisonous, combining with haemoglobin in the blood and prevents it from carrying oxygen.
Sulfur dioxide:- Sources- combustion of fuels, natural gas and sulfide ores e.g. zinc blende (ZnS) in the extraction of zinc.
Adverse effects-acid rain which causes corrosion to metal structures, buildings and statues made of carbonate rocks, damage to aquatic organisms. Pollutes crops and water supplies, irritates lungs, throats and eyes.

Question 3

What is nitrogen and sulphur dioxide used to make?

Answer 3

Nitrogen dioxide and sulphur dioxide can dissolve in rainwater to form nitric acid sulphuric acid respectively. These two gases cause acid rain.

Question 4

How do greenhouse gases cause global warming?

Answer 4

The sun’s radiation warms the earth. Some of the heat that should escape gets trapped by the greenhouse gases and raise the temperature of the earth, hence global warming.

Question 5

State two ways to reduce environmental impact of pollutant for climate change

Answer 5

• Plant trees
• Reduce livestock in farming
• Decrease use of fossil fuels

Question 6

State two ways to reduce environmental impact of pollutant for acid rain

Answer 6

• use catalytic converters in vehicles

- reduce emission of sulfur dioxide by using low-sulfur fuels

Question 7

What is a catalytic converter

Answer 7

This is a device that is fitted to the exhaust pipe of a car to clean up exhaust fumes

Question 8

What is rusting?

Answer 8

Rust is a chemical reaction between iron, water and oxygen to form the compound iron (III) oxide
Oxygen and water must be present for rust to occur