Environmental Problems Flashcards
What is 90% of crude oil used as?
A fuel
How is crude oil used as a fuel?
It is burnt to release the energy stored inside it
What are the 2 most prevalent things to burn crude oil as a fuel? What for?
- Power stations - electricity
- Cars - power engines
What other substance can be burned as a fuel?
Pure hydrogen
What is an advantage of using pure hydrogen as a fuel instead of crude oil?
Water vapour is the only substance produced from burning hydrogen
Crude oil produces other problematic substances
What do most fuels (e.g. iol and coil) contain? (2)
- Carbon
- Hydrogen
What happens when oil or coal combust?
The carbon and hydrogen oxidise to form carbon dioxide and water vapour
Equation for the oxidisation of hydrogen and carbon in combustion of fossil fuels
hydrogen + oxygen -> carbon dioxide + water vapour (+ heat energy)
What 3 things are produced when fossil fuels combust?
Heat energy
What happens to the carbon dioxide and water vapour produced during the oxidisation of hydrogen and carbon?
They are released into the atmosphere
If a fuel has sulfur impurities, what else will be produced when it combusts?
Sulfur dioxide
What else will be formed if a fuel combusts at a high temperature?
Oxides of nitrogen
What happens when there’s plenty of oxygen when a fuel burns - what is this called?
ALL the fuel burns
Complete combustion
What happens if there’s not enough oxygen during the combustion of fossil fuels?
What is this called?
NOT all the fuel burns
Partial combustion
During partial combustion, what is produced? (3)
1. Particulates of soot (carbon)
- Unburnt fuel
- Carbon monoxide
What is one of the gases that cause acid rain?
Sulfur dioxide
When sulfur dioxide mixes with ____ it forms ____ ____ ____ .
This then falls as ____ ____ .
When sulfur dioxide mixes with clouds it forms dilute sulfuric acid.
This then falls as acid rain.
What is the other substance that can be produced from burning fossil fuels, and causes acid rain?
Oxides of nitrogen
What are the 4 negative impacts of acid rain?
- Changes acidity in lakes - kills many plants and animals
- Kills trees
- Damages limestone buildings and stone statues
- Possible links between acid rain and human health problems
The benefits of ____ and ____ have to be balanced against the ____ ____ .
The benefits of electricty and travel have to be balanced against the environmental impacts.
What have governments done in recognition of the importance of balancing the positives and negatives of using fossil fuels?
Made international agreements to reduce emissions of air pollutants such as sulfur dioxide
How can we reduce acid rain?
By reducing suflur emissions
How can we reduce sulfur emissions?
What is a disadvantage of this?
By removing sulfur impurities from fuel before it is burned
BUT
this costs more to do
What are 2 disadnavtages of removing sulfur impurities from fuel before it is burned?
- It costs more
- It takes more energy
Why does it take more energy to remove sulfur impurities from fuel before it is burned?
Why is this another disadvantage?
More fuel is burned to remove it
So more of the greenhouse gas carbon dioxide is released
What are starting to be replaced to reduce sulfur dioxide emissions, and with what?
petrol and diesel
with low-sulfur versions
What do power stations now have?
Why?
Acid Gas Scrubbers
To take out the harmful gases before they release their fumes into the atmosphere
What are the 3 ways of reducing acid rain?
- Removing sulfur impurities from fuel before it is burned
- Removing the harmful gaases from fumes before they are released into the atmosphere
- Reducing our use of fossil fuels
