Earth's atmosphere

The original atmosphere of the Earth was created by volcanoes and consisted mainly of which gas?

• Oxygen

• Water vapour

• Nitrogen

• Carbon dioxide

The original atmosphere of the Earth was created by volcanoes, which of the following gases was there none of in the early atmosphere?

• Oxygen

• Methane

• Nitrogen

• Carbon dioxide

Mars and Venus have atmospheres like that of the early Earth. Which gas are their atmosphere's mostly made from?

• Nitrogen

• Carbon dioxide

• Methane

• Water vapour

Explain how and why the level of carbon dioxide in the Earth's early atmosphere dropped significantly.

Explain how and why the level of oxygen in the Earth's atmosphere increased significantly about 2.7 billion years ago.

Which is the following statements is NOT true?

• The atmosphere is about one fifth oxygen

• The atmosphere contains small amounts of water vapour and noble gases

• The atmosphere is about 80% oxygen

• The atmosphere is about four fifths nitrogen

Earths atmosphere today contains about __% oxygen

Which statement explains why there is little evidence for the Earth's early atmosphere?

• There was nobody alive then

• The time scale is 4.6 billion years ago

• There are no written records

• The atmosphere has changed a lot since then

Which of the following lists contains three greenhouse gases?

• Methane

  Nitrogen

  Oxygen

• Water vapour

  Methane

  Carbon dioxide

• Methane

  Carbon dioxide

  Nitrogen

• Carbon dioxide

  Oxygen

  Water vapour

Which is the correct equation for photosynthesis?