Environmental problems

Question 1

What are the 2 main culprits for burning fossil fuels

Answer 1

Cars

Power stations - for electricity

Question 2

What happens to the carbon and hydrogen in fuels during combustion

Answer 2

They are oxidised

Question 3

What is the word equation for the oxidisation of hydrogen and carbon during combustion

Answer 3

Hydrogen + Oxygen -> Carbon dioxide + Water vapour

Question 4

Oxides of what may also be produced?

Answer 4

Nitrogen

Question 5

When are oxides of nitrogen produced

Answer 5

If a fuel is burned at a really high temperature

Question 6

What happens if the fuel contains sulphur impurities

Answer 6

It will be released as sulphur dioxide

Question 7

What is partial combustion

Answer 7

Where there isn’t enough oxygen so not all the fuel is burned

Question 8

What is complete combustion

Answer 8

When there is plenty of oxygen so all fuel is burned

Question 9

What 3 things are released in partial combustion

Answer 9

Particulates of soot
Carbon monoxide
Unburnt fuel

Question 10

What does sulphur dioxide cause

Answer 10

Acid rain

Question 11

How does sulphur dioxide cause acid rain

Answer 11

Reacts with the clouds to form dilute sulphuric acid which falls as acid rain

Question 12

What 3 things does acid rain do

Answer 12

Causes lakes to become acidic, killing marine life
Destroys limestone buildings and stone statues
Causes trees to be killed

Question 13

What are 3ways we can reduce acid rain

Answer 13

Reduce fossil fuels use
Remove sulphur from fuels before they’re burnt
Replace petrol and diesel with low-sulphur versions

Question 14

What are 2 disadvantages of removing sulphur from fuels before they’re burnt

Answer 14

Costs more

Uses more energy

Question 15

What is happening to the amount of co2 in the earths atmosphere

Answer 15

Increasing

Question 16

Why do scientists think co2 levels are increasing

Answer 16

Fossil fuels use

Question 17

What has the increase in Co2 in the atmosphere caused

Answer 17

Global warming - the average temperature of the earth has increased

Question 18

What have scientists found about the level of sunlight reaching the earth

Answer 18

There is 25% less sunlight reaching the earth than 50 years ago

Question 19

Why do the scientists think global dimming is happening

Answer 19

Particles of soot and ash are causing the formation of more cloud and reflecting the suns light back into space

Question 20

What are the 3 alternatives to burning fossil fuels

Answer 20

Ethanol
Biodiesel
Hydrogen gas

Question 21

Why is ethanol known as a biofuel

Answer 21

Produced from plant material

Question 22

What is ethanol used for

Answer 22

Power cars in some places

Question 23

2 Pros of using ethanol as an alternative to burning fossil fuels

Answer 23

Carbon-neutral as carbon burned is taken in by plant

Only other product is water

Question 24

2 Cons of using ethanol as an alternative to burning fossil fuels

Answer 24

Not widely available

Engines need converted before they can be used

Question 25

3 Pros of using biodiesel as an alternative to burning fossil fuels

Answer 25

Engines don't need converted Produces less particulates and soot Carbon-neutral

Question 26

2 Cons of using biodiesel as an alternative to burning fossil fuels

Answer 26

Expensive | Can't make enough to completely replace diesel

Question 27

A pro of using hydrogen gas as an alternative to burning fossil fuels

Answer 27

Very clean - it only reacts with oxygen in the air to form water

Question 28

2 Cons of using hydrogen gas as an alternative to burning fossil fuels

Answer 28

Special, expensive engine needed | No widely available

Question 29

Where is the hydrogen used as an alternative fuel from

Answer 29

Electrolysis of water

Question 30

How do you get biodiesel

Answer 30

Produced from vegetable oils such as Rapeseed and soybean oil

Question 31

How does biodiesel work

Answer 31

Mix it with ordinary diesel and use to run a diesel engine