Which gases make up the atmosphere?

What are the relative proportions of the main gases in the atmosphere?

How was the Earth's early atmosphere formed?

What happened when the Earth cooled?

What impact did the evolution of photosynthesising organisms have on the atmosphere?

How has human activity changed the composition of the atmosphere?

How are some pollutants harmful to humans?

How are some pollutants harmful to the environment?

What is coal mainly made up from?

What are petrol, diesel, and oil mainly compounds of?

What happens when fuels burn?

What is oxidation?

What is reduction?

Fuels burn more _________ in _________ than in ________.

How does burning fossil fuels in power stations and in transport pollute the atmosphere?

How can atmospheric pollution caused by power station be reduced?

How can sulfur dioxide be removed from flue gases?

How can particulates be removed from power stations?

What is the only way of producing less carbon dioxide?

How can atmospheric pollution caused by exhaust emissions be reduced?

How does a catalytic converter work?