The atmosphere assessment

1. Which gas was thought to be a major part of the early atmosphere?

• Carbon dioxide
• Nitrogen
• Oxygen

2. Which of these planets has an atmosphere most similar to what scientists thought the Earth's early atmosphere was like?

• Mercury
• Venus
• Saturn

3. In the modern day atmosphere, what is the approximate percentage of nitrogen?

• 0.04%
• 20%
• 80%

4. What biochemical process absorbs carbon dioxide from the atmosphere and replaces it with oxygen?

• respiration
• photosynthesis

5. Which process removed carbon dioxide from the atmosphere?

• Formation of igneous rocks
• Formation of sedimentary rocks
• Formation of metamorphic rocks

6. Which gas produced by the combustion of fossil fuels causes acid rain?

• Nitrogen
• Sulfur dioxide
• Ozone

7. What is the laboratory test for oxygen?

• Puts out a glowing splint
• Makes a squeaky pop sound with a burning splint
• Relights a glowing splint

8. Which two main processes take place naturally and, when combined, help to keep the level of oxygen in our atmosphere nearly constant?

• Respiration and combustion
• Photosynthesis and combustion
• Respiration and photosynthesis

9. Acid rain is caused by the reaction of rain water with which pollutant gas?

• Carbon dioxide
• Sulfur dioxide
• Argon

10. Which test can be used to positively identify carbon dioxide gas?

• Put the flame of a burning splint into the test tube full of carbon dioxide – the flame will be extinguished
• Bubble the carbon dioxide through limewater – the limewater will change colour from clear colourless to milky white
• Put the glowing end of a recently extinguished splint into a test tube full of carbon dioxide – the splint will re-ignite