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Crude oil
a mixture of hydrocarbon molecules
Complete combustion
when there is plenty of oxygen, hydrocarbons burn to produce only carbon dioxide and water
Incomplete combustion
if there isn't enough oxygen, hydrocarbons burn to produce carbon dioxide, water, carbon and carbon monoxide
Carbon monoxide
odourless, colourless and very poisonous gas that is produced from incomplete combustion
Sulfur dioxide
causes acid rain when it mixes with clouds to form dilute sulfuric acid.
Acid rain
causes lakes to become acidic and many plants and animals die as a result, it also kills trees and damages limestone buildings.
Acid rain prevention
using acid gas scrubbers in power stations and cars now have catalytic converters to clean up exhaust gases
alternatives to fossil fuels that are better because they are made from chemicals obtained from living things
a biofuel made by microorganisms due to this it is renewable
a biofuel made from sugar that can be used as fuel
Fuel Cells
an electrical cell that's supplied with a fuel and oxygen and uses energy from the reaction between them to generate electricity
Fuel cell advantages
more efficient, fewer places for energy to be lost as heat, no energy is lost through friction and they don't produce any conventional pollutants
chains of carbon atoms with single bonds between them. They are called saturated hydrocarbons, they don't turn bromine water colourless and they won't form polymers - no spare bonds
chains of carbon atoms with one or more double bonds. They are called unsaturated hydrocarbons, they turn bromine water colourless and they form polymers - they have free bonds
splitting up long chains of hydrocarbons into smaller hydrocarbons
Conditions for cracking
heat and a catalyst
small molecules
long-chain molecules