These cards are for the OCR 21st Century Science Course, and they are complete.
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What is the atmosphere?

Name the major two gases and their percentages in normal air quality.

What are the main air pollutants?
(There are 5!)

How is air quality measured?

What 2 factors influence air quality, with examples?

What was earth's early atmosphere like?

Why is it important to repeat an experiment?

How do you know if your data is accurate?

What is a change that forms a new chemical called?

When coal is burned in a power station, it produces CO2. Why is this?

In a gas-fired power station CO2 and H2O are produced - where does the water come from?

Why does sulfur dioxide (SO2) sometimes form when coal or gas are burned?

In a reaction what are carbon and oxygen called? What is carbon dioxide called?

What is a correlation?

What is a cause?

How does a catalytic converter work?

How is sulfur dioxide removed, as much as possible, from power station emissions? Aside from refining the material before burning?

How are particulates removed from waste gases?