Our Changing Planet

Question 1

Who came up with the idea of continental drift, were their ideas accepted?

Answer 1

Alfred Wegener in 1915

He couldn’t explain why the continents moved

Question 2

What was the earth’s early atmosphere like?

Answer 2

Volcanoes 4.5 billion years ago erupted and released

Carbon dioxide, water vapour and nitrogen

Question 3

What happened to the earth’s early atmosphere?

Answer 3

Water vapour condensed to form the oceans

Bacteria, plants and algae evolved which used co2 for photosynthesis which released oxygen into the atmosphere

Question 4

Explain the Miller-Urey experiment

Answer 4

They set up a replica of the earths early atmosphere and used a lightning spark to the gases to see what happened. Amino acids (proteins) are formed.

These formed a primordial soup which began life

Question 5

What else happened to the carbon dioxide in the early atmosphere?

Answer 5

Photosynthesis
Sedimentary rocks
Fossil fuels
Marine organisms

Question 6

What’s the atmosphere like now?

Answer 6

Nitrogen 78%
Oxygen 21%
Carbon dioxide 0.04%
Argon 0.9%
Mix of others

Question 7

Why can the gases in air be separated by fractional distillation?

Answer 7

It is a mixture of different substances with different boiling points