Chemistry Of The Atmosphere

Question 1

Proportions of gases in the atmosphere

Answer 1

78% nitrogen
21% oxygen
0.04% carbon dioxide
0.96% other gases

Question 2

How old is the earth

Answer 2

4.543 billion years

Question 3

How has oxygen and CO2 changed over time?

Answer 3

It was mainly CO2 with very little oxygen, mainly due to photosynthesis where plants absorb CO2 and release oxygen

Question 4

How is it believed that the early atmosphere was formed?

Answer 4

Gases from volcanoes because it is believed that the earth was mainly volcanic

Question 5

How did the CO2 level decrease 3.8 billion years ago

Answer 5

The water from the atmosphere condensed as the earth temperature decreased. CO2 dissolved in water

Question 6

Timeline

Answer 6

4 billion years ago- hydrosphere was formed
3.8 billion years ago- water from the atmosphere condensed
2 billion years ago- first oxygen in the atmosphere
1 billion years ago- first organisms started to photosynthesise
600 million years ago- ozone is strong enough to stop potentially lethal UV

Question 7

Limestone
Where does carbon in it come from
Carbon containing compound in it
Conditions to make sedimentary rocks like limestone

Answer 7

Shells and sediment cement together over time and store carbon in stone
Calcium Carbonate
Clear, warm, shallow waters

Question 8

Crude Oil
Where carbon comes from
Carbon containing compound
Conditions to make

Answer 8

Hydrocarbons- hydrogen and carbon have bonded
Hydrocarbons
Higher pressure causes more complex organisms to decompose

Question 9

Coal
Where carbon comes from
How long to form coal and oil
Conditions needed to make

Answer 9

Tissues of plants
Millions of years
Needs pressure and heat to turn ferns, plants and trees to coal

Question 10

Greenhouse effect

Answer 10

Where the warmth of the sun is trapped inside the atmosphere increasing the temperature of a planet

Question 11

Effect of greenhouse gases on wavelength

Answer 11

Earth absorbs radiation of most wavelengths then absorbs the radiation with short wavelengths and releases the wavelengths with long wavelengths. Some is absorbed by greenhouse gases and consequently the atmosphere increases temperature

Question 12

Methane and CO2 are released by

Answer 12

CO2- follow fuels, breathing

Methane- breakdown of organic matter

Question 13

Results of global warming

Answer 13

Increased temperature, average increased by over a degree since 1860s
Drought, has and will lead to inconsistent weather conditions
Polar icecaps melting, increase in temperate can lead to polar icecaps melting
Rising sea levels, melting of polar ice caps leads to rising sea levels and flooding of low level land, including cities

Question 14

Carbon footprint

Answer 14

The amount of CO2 released into the atmosphere because of the actions of a person or group

Question 15

Complete combustion

Answer 15

Fuel + oxygen —> CO2 and water

Question 16

Incomplete combustion

Answer 16

Fuel + insufficient oxygen —> carbon monoxide + carbon particulates + water

Question 17

Carbon dioxide

Answer 17

Formed through anaerobic respiration in plants and combustion
Causes greenhouse effect to trap heat and increase the overall temperature of the planet

Question 18

Carbon monoxide

Answer 18

Formed through the incomplete combustion of carbon

Affects the atmospheres ability to remove polluting gases from itself

Question 19

Carbon particulates

Answer 19

Also released through incomplete combustion

Strongly absorb sunlight so less reaches the ground

Question 20

Sulphur dioxide

Answer 20

Formed from the burning of fossil fuels and the smelting of mineral ores
Combines with water and air to form acid rain, can cause deforestation

Question 21

Nitrogen oxides

Answer 21

Formed by nitrogen reacting with oxygen during combustion

Known to react to form smog and acid rain