Hydrocarbon fuels are made from the elements carbon and hydrogen.
Coal, oil and natural gas (methane) are all
hydrocarbons.
When hydrocarbons burn they form carbon dioxide and
water, and release heat energy.
methane + oxygen → carbon dioxide + water
If there is not enough oxygen available, carbon monoxide or even soot is produced
Reactions
Displacement reactions happen when a metal displaces a less reactive metal from a solution. The
reaction gives out heat energy
• Two different metals put into acid can produce electrical energy
Oxidation reactions happen when something reacts with oxygen. Most oxidation reactions give out
heat energy
New Materials
Chemical reactions are used to make nearly all the materials around us. Plants make glucose
from carbon dioxide and water, using energy from sunlight.
Plants make all the chemicals they need using this glucose, together with water and mineral
salts. All the chemicals in our bodies are made from the food we eat, by chemical reactions that
happen in our cells.
New materials are being developed all the time. Some new materials have better properties than
older ones, or are cheaper to make.
New foods and drugs are also being developed. Once a new material has been discovered,
scientists have to work out how to make it in a factory, and how to make it into new products.
New drugs have to be tested to make sure they work and to check that they do not have any
harmful effects.