Environmental Problems Flashcards
Why do we burn fossil fuels?
To release the energy stored inside them.
What % of crude oil is used as fuel?
90%.
What do burning fossil fuels release?
Gases and particles.
Power stations burn what?
Huge amounts of fossil fuels to make electricity.
What is also another major culprit in burning fossil fuels?
Cars.
Most fuels such as crude oil and coal contain what?
Carbon and hydrogen.
What happens during combustion?
The carbon and hydrogen are oxidised so that carbon dioxide and water vapour are released into the atmosphere.
Energy (heat) is also produced.
What happens if the fuel contains sulphur impurities?
The sulphur will be released as sulphur dioxide when the fuel is burnt.
What will also form if the fuel is burned at high temperatures?
Oxides of nitrogen.
What happens when there’s plenty of oxygen?
All the fuel burns.
This is called complete combustion.
What happens when there’s not enough oxygen?
Some of the fuel doesn’t burn.
This is called partial combustion.
What happens during partial combustion?
Solid particles of soot and unburnt fuel are released.
Carbon monoxide is also released.
During partial combustion what are the solid particles called?
Particulates.
What is the soot during partial combustion?
Carbon.
What does sulphur dioxide?
Acid rain.
What happens when sulphur dioxide mixes with clouds?
It forms dilute sulphuric acid.
This then falls as acid rain.
Oxides of nitrogen cause acid rain by doing what?
Forming dilute nitric acid in clouds.
How does acid rain affect the environment?
Causes lakes to become acidic.
Many plants and animals die as a result.
Kills trees.
How does acid rain affect buildings?
If the building is limestone it will become damaged.
It also ruin statues.
What links have been suggested about acid rain?
Whether humans have health problems.
What has to be balanced?
The benefits of electricity and travel have to balance against the environmental impacts.
How do you reduce acid rain?
By reducing sulphur emissions.
What can happen before the fuels are burnt?
Most of the sulphur can be removed before fuels are burnt but it costs more and takes more energy.
Removing sulphur from fuels takes a lot of energy where does this come from?
From burning more fuel which releases more of the greenhouse gas carbon dioxide.
What are petrol and diesel starting to be replaced by?
Low-sulphur versions.
What do power stations use to take harmful gases out before they release their fumes into the atmosphere?
Acid Gas Scrubbers.
What is the simple way of reducing acid rain?
Reduce the usage of fossil fuels.
