What is fractional disillation?
Separating crude oil into different useful substances by evaporating it and cooling it up a tower
Why do different substances come out at different levels of a fractional distillation tower?
They have different boiling points
What is a complete combustion?
When hydrocarbons are burned and the only products are carbon dioxide and water
What is an incomplete combustion?
Hydrocarbon burns in a limited supply of oxygen
What determines a hydrocarbon’s properties?
Size
What are the properties of small hydrocarbons?
Lower boiling point
Easy to ignite
What is a pollutant?
Toxic substances that are produced when burning fossil fuels
What can be used as a clean, renewable fuel?
Hydrogen gas
What are the pros of using hydrogen gas as a fuel?
Clean
Renewable
What are the cons of using hydrogen gas as a fuel?
Expensive
Manufacturing it often uses energy from another source
Hard to store
Not widely available
Give examples of pollutants?
Carbon monoxide
Sulphur dioxide
Oxides of nitrogen
What does sulphur dioxide cause?
Acid rain
What can oxides of nitrogen contribute to?
Photochemical smog
What is photochemical smog?
Air pollution that can cause breathing difficulties
What is cracking?
Splitting up a long chain of hydrocarbons
What is a theory about how the atmosphere might have evolved?
Volcanoes gave out steam and carbon dioxide
Plants evolved and produced oxygen
Ozone layer allows evolution of complex animals
How does human activity affect the earth?
As the population increases, carbon dioxide increases, as more are respiring. Therefore, the earth is getting warmer
How does the greenhouse effect make the earth warmer?
Sun gives out electromagnetic radiation, which is absorbed by the earth
What causes climate change?
Increasing greenhouse gases
How is methane produced?
Digestive processes of livestock
What does the increase of methane cause?
Global warming