| What is a hydrocarbon? | Any compound formed from only carbon and hydrogen atoms |
| What is crude oil? | A mixture made up of hydrocarbons of different lengths |
| What happens to the properties of hydrocarbons as chain length increases? | Become more viscous, less volatile, less flammable, higher boiling points |
| What are alkanes? | Saturated compounds with a C-C single bond |
| What are the first 4 alkanes? | Methane, Ethane, Propane, Butane |
| Chemical formulas of first 4 alkanes | CH4, C2H6, C3H8, C4H10 |
| General formula for alkanes? | CnH2n+2 |
| What is the equation for complete combustion of a hydrocarbon? | Hydrocarbon + oxygen ---> carbon dioxide + water + energy |
| Method of fractional distillation [for Crude oil] | Oil is heated until most is a gas
Gases enter fractionating column
Longer hydrocarbons with higher boiling points condense back into liquids and drain out of column early near the bottom
Shorter hydrocarbons with lower boiling points condense and drain out later near the top of the column
Mixture is separated into fractions containing hydrocarbons with similar numbers of carbon atoms |
| Method of cracking [catalytic] | Vaporise long chain hydrocarbons
Vapour passed over hot powdered aluminium oxide as a catalyst
Molecules split apart on the surface of the catalyst |
| What are alkenes? | Unsaturated compounds that have a double C=C bond |
| What products are produced when alkenes undergo incomplete combustion? | Carbon and carbon monoxide |
| When is hydrogen added to an alkene? | In the presence of a catalyst |
| When is an alcohol formed? | When an alkene reacts with steam and water is added in the presence of a catalyst |
| What are the uses of alkenes? | Alcohols, plastics, fuels, detergents |
| What are polymers? | A molecule comprised of long chains of monomers |
| What is addition polymerisation? | Where unsaturated monomer molecules open up their double bonds and join together to form polymer chains |
| What are the first 4 alcohols? | Methanol, Ethanol, Propanol, Butanol |
| What are the formulas for the first 4 alcohols? | CH3OH, C2H5OH, C3H7OH, C4H9OH |
| What do alcohols form when deoxidised? | Carboxylic acids |
