Chemistry - Chemistry of the atmostphere

Question 1

How long have the proportions of the gasses in the atmosphere been like today

Answer 1

200 million years

Question 2

What are the gases and percentages found in today’s atmosphere

Answer 2

Nitrogen = 80%
Oxygen = 20%
Other gasses (including carbon dioxide, water vapour and Nobel gases( = <1%

Question 3

What timescale is evidence for the early atmosphere limited to

Answer 3

4.6 billion years

Question 4

What planets is the earth’s early atmosphere suggested to be like

Answer 4

Mars and Venus, consisted mainly of carbon dioxide and little or no oxygen

Question 5

What other gas were released by volcanoes

Answer 5

nitrogen methane and ammonia

Question 6

What are the four ways carbon dioxide is reduced

Answer 6

1. dissolved into the oceans
2. Plants took it in for photosynthesis
3. Carbonates precipitated producing sediments
4. locked in fossil fuels

Question 7

How did the percentage of oxygen increase in the early atmosphere

Answer 7

Algae and plants released it during photosynthesis

Question 8

Word equation for photosynthesis

Answer 8

Carbon dioxide + water -> glucose + oxygen

Question 9

Describe the greenhouse effect

Answer 9

1. first the sun emits short wavelength radiation which passes through the earths atmosphere and is absorbed by the earths surface
2. The earths surface emits any excess radiation as long wavelength radiation towards space.
3. some of the long wavelength radiation makes its way through the earths atmosphere however some do not as greenhouse gasses traps them.
4. this is then emitted to the earths surface causing it to heat up more resulting in the earths average temperature to increase.

Question 10

When did algae first appear

Answer 10

2.7 billion years ago

Question 11

What did the increase in oxygen from algae and plants lead to

Answer 11

Enables animals to evolve

Question 12

What useful substances have been formed as carbon dioxide increased

Answer 12

Limestone, coal, crude oil and natural gas

Question 13

What type of gas maintains the temperature on earth to be high enough to support life

Answer 13

Greenhouse gasses

Question 14

Examples of greenhouse gasses

Answer 14

Carbon dioxide
water vapour
methane

Question 15

What greenhouse gases are increased due to human activity

Answer 15

carbon dioxide increasing due to
-burning fossil fuels
-deforestation reducing carbon being taken In for photosynthesis

methane increasing due to
-farming cattle
-farming rice paddy fields
-landfill sites (rubbish decomposes and releases methane)
-\swamps

Question 16

What do scientists believe humans activity will do the temperature of the earth

Answer 16

Increase it, leading to climate change

Question 17

What is the temperature of the earth increasing normally referred to as

Answer 17

Global warming

Question 18

Why is it difficult to predict global warming

Answer 18

Based on simply models, speculation and opinion presented in media

Question 19

What is the issue with climate change presented in the media

Answer 19

Based on opinion, speculation, only parts of evidence and can be biased

Question 20

What is causing climate change

Answer 20

increase in average global temperature

Question 21

What are the main four potential effects of global change

Answer 21

glacier and polar ice caps melting
sea levels rising
patterns in rainfall changing
habitats changing

Question 22

What is the carbon footprint

Answer 22

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

Question 23

Major source of atmosphere pollutants

Answer 23

combustion of fuels

Question 24

what do most fuels contain

Answer 24

Carbon, hydrogen and some contain sulfur

Question 25

How can a carbon footprint be reduced

Answer 25

By reducing emissions of carbon dioxide and methane

Question 26

what do particulates contribute to

Answer 26

global dimming

Question 27

How are oxides of nitrogen produced when burning a full?

Answer 27

High temperature in car engines cause oxygen and nitrogen in the air to react

Question 28

How is sulfur dioxide produced when burning a fuel

Answer 28

Fuels contain sulfure as an impurity when the fuel is burnt the sulfur reacts with oxygen to form sulphur

Question 29

What do oxides of nitrogen and sulfur lead to

Answer 29

Acid rain respiratory problems

Question 30

What does carbon dioxide contribute to and why

Answer 30

global warming as it is a greenhouse gas

Question 31

What are the issues with the production of carbon monoxide

Answer 31

it is a toxic gas, prevents blood from carrying oxygen to your cells for respiration

Question 32

Why is it hard to detect if carbon monoxide is formed

Answer 32

it Is odourless and colourless so can’t be seen

Question 33

What theory is given for the earth’s early atmosphere?

Answer 33

1.First billion years intense volcanic activity released lots of carbon dioxide and water vapour (alongside other gases such as methane, nitrogen and ammonia)

2. When the Earth cooled the water vapour was able to cool and condensed to form oceans the oceans.
3. Overtime carbon dioxide levels started to decrease.
4. Algae and plants evolved
5. Oxygen levels started to increase and animals were
   then able to evolve

Question 34

Balanced symbol equation for photosynthesis

Answer 34

6CO2 + 6H2O -> C6 H12 O6 + 6O2

Question 35

How can we reduce carbon emissions?

Answer 35

reduce use of cars (cycle/walk instead)

eat less meat

ensure any trees cut down are replanted

recycle and reuse materials

install solar panels in your home

Question 36

What gases can be released into the atmosphere when fuel is burnt?

Answer 36

Carbon dioxide
Water vapour
Sulphur dioxide
Oxides of nitrogen
Others - Particulate (microscopic particles)

Question 37

Describe how natural deposits formed

Answer 37

Plankton

Mud

High temp and pressure

Question 38

Describe how natural deposits formed

Answer 38

Plankton

Mud

High temp and pressure