Chemistry Chapter 9 – The atmosphere – gases in the atmosphere, early atmosphere, oxygen and carbon dioxide State the difference between the Earth’s early atmosphere and the atmosphere today. Include percentages. Describe a theory for the Earth’s early atmosphere. Include any evidence for these theories. Explain how oxygen levels increased to the levels it is at today from the early atmosphere and give evidence. Give the processes and the word equation and balanced symbol equation for the gases remaining constant in the atmosphere aside from water vapour. Explain how carbon dioxide levels decreased to the levels it is at today from the early atmosphere and give evidence. Explain why the evidence for the early atmosphere is limited and the difference between proxy and direct evidence.

Chemistry Chapter 9 – The atmosphere – greenhouse gases, climate change and carbon footprint Explain why greenhouse gases are important. Include the effect of greenhouse gases and the radiation type in your answer. Describe the effects of climate change on the Earth. Include risks and environmental concerns. Describe and explain government methods for reducing the carbon footprint and why it is difficult to reduce the levels. Explain how human activities have lead to an increase in climate change. Describe what carbon footprint is and how we can reduce our own personal carbon footprint.

Chemistry Chapter 9 – The atmosphere – atmospheric pollutants from fuels, properties and effects and maths Give an equation for complete and incomplete combustion of fuels. State the differences between the two. Describe how oxides of nitrogen are caused, how it can be reduced and the effect of it. Describe how sulphur dioxide is caused, how it can be reduced and the effect of it. Describe how carbon monoxide is caused , how it can be reduced and the effect of it. Describe how particulates are caused, how it can be reduced and the effect of it. State the equation for percentage yield. Draw a pie chart to show the composition of air .