Chemistry of the Atmosphere

Question 1

What are the proportions of gases in the modern atmosphere?

Answer 1

80% Nitrogen
20% oxygen
small proportions of C02 and water vapour

This has been the same for around 200 million years

Question 2

What is one theory of the formation of the earths atmosphere?

Answer 2

During 1st billion years there was intense volcanic activity which released nitrogen and gases and formed the early atmosphere

water vapour condenses to from the first oceans

Question 3

What were the main components of the earths early atmosphere?

Answer 3

mainly carbon dioxide
little or no oxygen
Nitrogen, methane, and ammonia maybe in small amounts

similar to mars and venus today (mainly co2 with little or no oxygen

Question 4

What affect did the formation of oceans have on the early atmosphere?

Answer 4

when oceans formed CO2 dissolved in the oceans and formed carbonates which reduced the carbon dioxidde in the atmosphere

Question 5

How did oxygen accumalate in the earths atmosphere?

Answer 5

Algae and plants produced oxygen through photosynthesis
6CO2 + 6H20 → C6H12O6 + 6CO2

Oxygen first appeared around 2.7 billion yeras ago
Oxygen increased over time due to plant evolution - this enabled animals to evolve

Question 6

How did algae and plants impact the percentage of carbon dioxide in the atmosphere?

Answer 6

Algae and plants decreased the percentage of carbon dioxide through photosynthesis

CO2 levels further reduced due to formation of sedimentary rocks and fossil fuels (coal,crude oil and natural gas)

Question 7

What are the greenhouse gases responsible for maintaining temperatures on Earth?

Answer 7

Water vapor, carbon dioxide, and methane

Question 8

What does the greenhouse effect involve?

Answer 8

• interaction of short and long wavelength radiation with matter
• trap some of the heat energy from the Sun, preventing it from escaping back into space
• maintaining Earth’s temperature suitable for life

Question 9

What are two human activities that contribute to increased levels of carbon dioxide in the atmosphere?

Answer 9

Deforestation and burning fossil fuels, such as coal and oil

Question 10

How does agriculture contribute to higher methane levels, a greenhouse gas?

Answer 10

Agricultural practices, including livestock farming and rice cultivation, release methane into the atmosphere

Question 11

What are the consequences of elevated levels of greenhouse gases for Earth’s climate?

Answer 11

Increased surface temperatures and global climate change

Question 12

Why is modeling global climate change challenging?

Answer 12

• Global climate systems are complex, leading to difficulties in creating accurate models
• Simplified models may be biased or incomplete

Question 13

What is the importance of relying on peer-reviewed scientific evidence regarding climate change?

Answer 13

• Peer-reviewed evidence provides a reliable basis for understanding climate change
• media representations may oversimplify or be biased

Question 14

What is a major cause of climate change?

Answer 14

An increase in average global temperature

Question 15

Name four potential effects of global climate change

Answer 15

• Rising sea levels
• Increased frequency of extreme weather events
• Changes in precipitation patterns
• Impact on ecosystems and biodiversity

Question 16

What factors should be discussed when evaluating the implications of global climate change?

Answer 16

• Scale of the impact
• Associated risks
• Environmental consequences

Question 17

Why is the rising sea level considered a potential effect of climate change?

Answer 17

Melting polar ice caps and glaciers contribute to the rise in sea levels, posing a threat to coastal areas

Question 18

What is the carbon footprint?

Answer 18

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

Question 19

How can the carbon footprint be reduced?

Answer 19

By reducing emissions of carbon dioxide and methane

Question 20

What are the gases released into the atmosphere when a fuel is burned?

Answer 20

carbon dioxide
water vapor
carbon monoxide
sulfur dioxide
oxides of nitrogen

unburned hydrocarbons may be released forming particulates in the atmosphere

Question 21

What are the harmful effects of carbon monoxide, sulfur dioxide, oxides of nitrogen, and particulates released during fuel combustion?

Answer 21

• carbon monoxide -t oxic gas, colorless, and odorless.
• sulfur dioxide and oxides of nitrogen- cause respiratory problems, contributes to acid rain.
• particulates- contributes to global dimming, pose health problems for humans