Chemistry Of The Atmosphere

Question 1

What is the percentage of nitrogen in our atmosphere?

Answer 1

80%

Question 2

What is the percentage of oxygen in our atmosphere?

Answer 2

20%

Question 3

What other gases are in the atmosphere in small proportions?

Answer 3

Carbon dioxide, water vapour and noble gases

Question 4

Why is the evidence for Earth’s early atmosphere limited?

Answer 4

Because it formed so long ago

Question 5

How long ago did the early atmosphere form?

Answer 5

4.6 billion years

Question 6

How do we think the Earth’s early atmosphere formed?

Answer 6

Volcanic activity that released gases

Question 7

How do we think the oceans formed?

Answer 7

As the earth cooled, water vapour condensed

Question 8

What other planets atmospheres may Earth’s have been like in the past?

Answer 8

Mars and Venus

Question 9

How do we think nitrogen got into the atmosphere?

Answer 9

Volcanic activity

Question 10

What other gases could have been in the early atmosphere in small proportions?

Answer 10

Methane and ammonia

Question 11

Why did the formation of the oceans cause carbon dioxide levels to decrease?

Answer 11

Carbon dioxide dissolved in the water and carbonates precipitated producing sediments

Question 12

How is oxygen released into the atmosphere?

Answer 12

Photosynthesis

Question 13

What is the word equation for photosynthesis?

Answer 13

Carbon dioxide+Water-> Glucose+Oxygen

Question 14

What is the formula equation for photosynthesis?

Answer 14

6CO2+6H2O-> C6H12O6+6O2

Question 15

When did algae first appear on Earth?

Answer 15

2.7 billion years

Question 16

How long did it take for oxygen levels to build up so that animals could evolve?

Answer 16

A billion years

Question 17

Why did the percentage of carbon dioxide decrease further when plants evolved?

Answer 17

Photosynthesis removed it from the atmosphere. It became locked in sedimentary rocks and in fossil fuels

Question 18

Why are some greenhouse gases in the atmosphere important?

Answer 18

They maintain temperatures on Earth high enough to support life

Question 19

What are examples of greenhouse gases?

Answer 19

Water vapour, carbon dioxide and methane

Question 20

What human activities increase the amount of carbon dioxide in the atmosphere?

Answer 20

Burning fossil fuels and deforestation

Question 21

What human activities increase the amount of methane in the atmosphere?

Answer 21

Farming cattle, agriculture and dumping waste in landfills

Question 22

What are the potential effects of global climate change?

Answer 22

Ice caps melting, sea levels rising, patterns of rainfall changing and habitats changing

Question 23

What is the carbon footprint?

Answer 23

The total amount of carbon dioxide and other greenhouse gases emitted over the full cycle of a product, service or event

Question 24

What is a major source of atmospheric pollutants?

Answer 24

Burning fossil fuels

Question 25

What gases can be released when a fuel is burned?

Answer 25

Carbon dioxide, water vapour, carbon monoxide, sulfur dioxide and oxides of nitrogen

Question 26

Why is sulfur dioxide produced when a fossil fuel is burned?

Answer 26

The fuels contain some sulfur atoms

Question 27

What is carbon monoxide?

Answer 27

A toxic colourless, odourless gas

Question 28

What problems does sulfur dioxide cause?

Answer 28

Respiratory problems and acid rain

Question 29

What problems do nitrogen oxides cause?

Answer 29

Respiratory problems and acid rain

Question 30

What problems do particulates cause?

Answer 30

Global dimming and health problems in humans