Different Types of Chemical Reactions (Part 2) Unit 2 Topic 3

Question 1

Proportion of gases in the atmosphere?

Oxygen, Nitrogen, Argon, CO2

Answer 1

Oxygen = 21%
Nitrogen = 78%
Argon = 0.9%
Carbon Dioxide = 0.037%

Question 2

How does global warming happen?

Answer 2

Human activity (burning fossil fuels) increases carbon dioxide levels and create blanket around earth which traps heat.

Question 3

What is the current average temp of the earth?

What was the current average temp of the earth 2.7 billion years ago?

Answer 3

14c

70c

Question 4

Why was the average temp of the earth so high?

Answer 4

Intense volcanic activity releases large quantities o carbon dioxide.

Question 5

How did the CO2 level of the earth decrease?

Answer 5

Bacteria and plants turned it into carbonates, organic material and oxygen via photosynthesis.

Question 6

What has the rise in temperature in the last 100 years caused?
How much has it raised?

Answer 6

1c

Flooding + destruction of habitats,

Question 7

Who created theory of Continental Drift + when?

Answer 7

1912

Alfred Wegener

Question 8

What is meant by the theory of continental drift?

Answer 8

Originally continents joined in single land mass, millions of years ago they started to break up and form todays continents

Question 9

What is the current theory of plate tectonics?

Answer 9

Continents can move because there are convectional currents in the mantle

Question 10

What causes an earthquake?

Answer 10

Stresses and strains when 2 continental plates slide past each other or 1 slides under another. They may bend and forces are suddenly released which causes ground to shake violently and cracks develop in ground.

Question 11

What causes a volcano?

Answer 11

Plates move apart. Causes earth’s crust to be stretched and it may crack so molten magma and gases can escape and create a volcano.