C6.3

Question 1

What three substances make up 99.9% of the atmosphere

Answer 1

These are oxygen, nitrogen and argon. The smaller percentage is made up by carbon dioxide and water vapour.

Question 2

How did the earth’s atmosphere

Answer 2

Lots of volcanic activity during its early years releasing lots of carbon dioxide and water vapour. As the earth cooled the water vapour formed oceans and the carbon dioxide stayed in the atmosphere.

Question 3

What is the second stage of the earth’s atmosphere

Answer 3

Plants then photosynthesised absorbing CO2 and releasing O2

Question 4

What is the 3rd stage of the formation of the earth’s atmosphere

Answer 4

Photosynthesis reduced the amount of CO2 in the atmosphere. It also released oxygen. The oxygen reacted with rocks to form metal oxides, As all the metals were oxidised, free oxygen accumulated in the atmosphere. Forming an oxygen rich atmosphere.

Question 5

What are pollutants

Answer 5

Pollutants are substances released into the atmosphere that may harm living things.

Question 6

How are atmospheric pollutants released into the air

Answer 6

They are released into the air because of burning fossil fuels these are carbon monoxide, particulates, oxides of nitrogen and sulphur dioxide.

Question 7

When is carbon monoxide produced and characteristics of it

Answer 7

It’s produced during incomplete combustion of fuels. CO is a toxic and odourless gas.

Question 8

What are particulates and where are they produced

Answer 8

Particulates are small particles. They are produced in industrial processes such as metal extraction. They are produced in incomplete combustion.

Question 9

When do nitrogen and oxygen react together

Answer 9

They react at high temperatures in vehicle engines producing NO and NO2.

Question 10

What do nitrogen oxides do

Answer 10

Nitrogen oxides dissolve in the moisture in clouds forming an acidic solution which falls as acid rain.

Question 11

What are the effects of particulates

Answer 11

They settle in the lungs when breathed in. This causes diseases such as bronchitis and other breathing problems and increasing chance of heart disease.

Question 12

Impacts of carbon monoxide

Answer 12

When breathed in it attaches to haemoglobin reducing the amount of oxygen the bloodstream can carry. Causing drowsiness and difficulty breathing.

Question 13

What do fossil fuels contain

Answer 13

Fossil fuels contain small amounts of sulphur which when burnt forms sulphur dioxide, this can cause acid rain and breathing difficulties.

Question 14

What do greenhouse gases do

Answer 14

Greenhouse gases such as CO2 and CH4 absorb infrared radiation by the earth’s surface and then emit it in all directions.

Question 15

What is the greenhouse effect essential for

Answer 15

The greenhouse effect is essential for life as it keeps it warm enough for living things to exist.

Question 16

When is Carbon dioxide and methane released into the atmosphere

Answer 16

It is released into the atmosphere as a result of the burning of fossil fuels. Methane is released from farming.

Question 17

What does the release of the additional gases do

Answer 17

The release of these additional gases cause an enhanced greenhouse gas effect, increasing the temperature of the earth’ surface.

Question 18

Impacts of global warming

Answer 18

Global warming melts ice caps causing rising sea levels. Climate change brings altered weather patterns.

Question 19

How carbon emissions be reduced

Answer 19

Reduced consumption of fossil fuels
Use of renewable energy resources
Use of carbon capture

Question 20

Where does tap water originally come from

Answer 20

Tap water originally comes from water stored in lakes, reservoirs or aquifers. It may also have come from rivers or waste water. Water from these sources contain microorganisms and many different substances.

Question 21

What is in the water

Answer 21

.Insoluble materials such as leaves and particles from rocks and soil
.Soluble substance such as salts and pollutants such as pesticides and fertilisers

Question 22

Where are these removed

Answer 22

Most of these are removed at treatment facilities

Question 23

What is the first stage of making tap water

Answer 23

Water enters the water treatment works, it passes through a screen. This is made from bars of metal placed close together. These catch large objects such as leaves and twigs.

Question 24

What is the second stage of making tap water

Answer 24

Settlement tank - sand and soil settle out

Question 25

What is the third stage of making tap water

Answer 25

Aluminium sulphate and lime are added to the water. Small particles of dirt clump together so that they sink to the bottom of the water. The sludge that collects this is dumped in a landfill where it forms mud.

Question 26

What is the fourth stage of making tap water

Answer 26

The water is passed through a special filter made of fine sand. This removes any remaining particles of mud or grit so the water is clear.

Question 27

What is the fifth stage of making tap water

Answer 27

Although, the water now looks clean, it may still contain harmful bacteria. A small amount of chlorine is added the water to kill the bacteria.

Question 28

What is the sixth stage of making tap water

Answer 28

The PH of the water is checked and corrected so that it is neutral. The water is then stored in large tanks and service reservoirs, ready to be pumped to homes, schools, offices and factories.

Question 29

How is seawater converted into tap water

Answer 29

Seawater contains high concentrations of dissolved salts. To make this water potable the salt must be removed in a process called desalination.

Question 30

What is the process that desalination use

Answer 30

It uses “reverse osmosis”, “special ulttrafillers” to filter out the salts.