Organic Chemistry

• Hydrocarbons only contain carbon and hydrogen
• Alkanes have a single C-C bond
• The first four alkanes are methane, ethane, propane and butane
• Methane- CH4
• Ethane- C2H6
• Propane- C3H8
• Butane- C4H10
• The shorter a chain of hydrocarbons, the more viscous it is
• Shorter hydrocarbons are more flammable
• Complete Combustion: The burning of a fuel in oxygen to produce carbon dioxide and water.
• During combustion, a hydrocarbon is oxidised
• Crude Oil is a fossil fuel formed from the remains of ancient plants and animals.
• Longer hydrocarbons have high boiling points
• Fractional Distillation uses a temperature gradient to sort crude oil
• Homologous series: a group of compounds that have the same functional group and the same general formula
• Cracking means splitting up long chain hydrocarbons into smaller molecules.
• Smaller hydrocarbons are more useful
• Cracking a thermal decomposition reaction
• 2 types of cracking: Catalytic Cracking and Steam Cracking
• Catalytic Cracking requires a catalyst
• Steam Cracking requires hydrocarbons to be heated to very high temperatures and mixed with steam
• Alkenes have a double C=C bond
• Alkenes are unsaturated
• Ethene- C2H4
• Propene- C3H6
• Butene- C4H8
• Alkenes burn with a smoky flame
• Incomplete Combustion produce carbon dioxide, water and carbon monoxide
• Carbon Monoxide is poisonous
• Incomplete combustion results in less energy being released
• Addition of hydrogen to a alkene is known as hydrogenation
• When alkenes react with steam, an alcohol is formed
• Alcohols have the functional group -OH
• Bromine Water is used to test for alkenes
• If an alkene is present, bromine water will turn from orange-brown to colourless
• Polymers is a long chain of monomers joined together by covalent bonds
• Methanol- CH3OH
• Ethanol- C2H5OH
• Propanol- C3H8OH
• Butanol- C4H9OH