Chemistry - Chemistry of the Atmosphere

Question 1

Roughly how old is the planet Earth

Answer 1

Around 4.6 billion years old

Question 2

What percentage of the air does Nitrogen now make up

Answer 2

Around 80%

Question 3

What percentage of the air does Oxygen now make up

Answer 3

Around 20%

Question 4

What gases contribute less than one percent of the earths atmosphere

Answer 4

Carbon Dioxide and Argon

Question 5

In the first billion years the gases that formed Earths early atmosphere cam mainly from which source

Answer 5

Volcanic activity

Question 6

During the first billion years, which gases were released from volcanoes

Answer 6

Water vapour , carbon dioxide and small amounts of methane and ammonia

Question 7

What happened to water vapour when the earth began to cool

Answer 7

The water vapour condensed into liquid water and formed the oceans

Question 8

What happened to the carbon dioxide when the oceans formed

Answer 8

Carbon dioxide dissolved in the water and carbonates were precipitated, producing sediments.

Question 9

How did the cooling of the earth effect the levels of gases in the atmosphere

Answer 9

Dramatically reduced the amounts of water vapour and carbon dioxide in the atmosphere

Question 10

Starting 2.7 billion years ago, which process started to increase the amount of oxygen in the atmosphere, and further decreased tge amount of carbon dioxide

Answer 10

Photosynthesis by plants and algae

Question 11

What happened to carbon as photosynthetic organisms such as plants and algae began to die

Answer 11

The carbon they contained became trapped in sedimentary rocks and fossil fuels

Question 12

What happened to the seabed when plants animals and marine life died

Answer 12

The organisms would fall to the seabed and get buried by layers pf sediments. Over billions of years they became compressed and form sedimentary rocks, oil and gas

Question 13

What is the atmosphere

Answer 13

a layer of gases surrounding the Earth that is held in place by gravity

Question 14

Name the greenhouses gases

Answer 14

Methane
Carbon dioxide
Water vapour

Question 15

Describe the greenhouse effect

Answer 15

Solar radiation from the sun passes through the atmosphere and hits the earth. Some of the energy is reflected straight back towards space, and some of it is absorbed by the earth and the re-emitted towards space. Some of the energy makes it all the way to space, but much of it is absorbed by small molecules called greenhouse gases. These molecules then reemit the energy and the whole process of absorption and emission happens over and over again. This trapped energy keeps the atmosphere warmer and more stable than it otherwise would be

Question 16

How are global warming and climate change different?

Answer 16

Global warming refers to the overall increase in the Earth’s temperature where as climate change is a a consequence of global warming and refers to the effects on the climate, such as large-scale shifts in weather patterns.

Question 17

What is one affect of global warming

Answer 17

The melting of the icecaps. This will increase the volume of water in the ocean and could lead to seasonal flooding, or the submersion of entire islands. This is made worse by the fact that water expands when it is heated, so it will also increase in volume.

Question 18

What’s the difference between the climate and weather?

Answer 18

Weather refers to short term atmospheric conditions, like whether it’s raining or sunny on a particular day where as climate describes the typical weather conditions in an entire region for a very long time.

Question 19

What is the carbon footprint

Answer 19

The amount of greenhouse gases emitted over the full life cycle of a product, service or event

Question 20

Factors you would need to take into account when calculating carbon footprint

Answer 20

• The manufacturing process
• How it’s disposed of
• How all the raw materials were sourced

Question 21

General ways we can reduce the carbon footprint of a product

Answer 21

-Create it using fewer, or more sustainable, raw materials
-Use a more efficient manufacturing process (e.g. less energy or less waste)
-Use renewable energy resources (e.g. wind, solar, or nuclear)
-Recycle it, rather than disposing of it in landfill

Question 22

Why is it hard to use more renewable energy resources, rather than fossil fuels?

Answer 22

Renewable energy resources are more expensive
Many of our existing products require greenhouse gasses

Question 23

Pro and con of carbon capture technology

Answer 23

Allows us to trap carbon and store it deep underground. But it is very expensive

Question 24

Equation for the complete combustion of hydrocarbons

Answer 24

Hydrocarbon + oxygen ———> carbon dioxide + water

Question 25

Incomplete combustion can lead to the formation of what

Answer 25

Small particles of carbon which are called “particulates” or “soot”

Question 26

Adverse effects of particulates

Answer 26

-Cause respiratory problems as the particles damage our lungs
-Forms clouds of smog which reflect light back to space

Question 27

Which two products are formed from the incomplete combustion of hydrocarbons

Answer 27

Particulates and carbon monoxide

Question 28

Describe why carbon monoxide is harmful for humans

Answer 28

When we breathe in carbon monoxide it diffuses into our bloodstream, and binds to our haemoglobin. This reduces the amount of oxygen that haemoglobin can carry so less oxygen is transported to the tissues, which can cause symptoms such as fainting, coma and death

Question 29

When burning fossil fuels how is sulphur dioxide formed?

Answer 29

Sulphur is an impurity in some fossil fuels and is oxidised when they’re combusted

Question 30

When burning fossil fuels in an engine how are nitrogen oxides formed?

Answer 30

Nitrogen from the air is oxidised at the high temperature inside the engine

Question 31

What oxides can form acid rain

Answer 31

Nitrogen oxide and sulphur dioxide

Question 32

What are adverse effects of acid rain

Answer 32

Makes our soil more acidic, which harms plants
It damages certain buildings and statues

Question 33

Other than acid rain, what problem is caused by sulphur dioxide and other oxides of nitrogen?

Answer 33

Respiratory problems in humans