| Why are alkanes generally unreactive compounds | Very small difference in electronegativity between carbon and hydrogen. Their atoms share the pair of electrons in the single covalent bond almost equally. Therefore, alkane molecules are non-polar, so they are not attacked by nucleophiles or electrophiles |
| Alkanes are often used as fuels. We burn them for many reasons. Name 4. | 1. Generate electricity in power stations
2. Heat homes, cook our food
3. Provide energy needed in industrial processes
4. Provide fuel ships, aeroplanes, cars |
| Motor vehicles can now be fitted with catalytic converters in their exhaust systems. Once warmed up, a catalytic converter can cause the following reaction to take place | Oxidation of carbon monoxide to form carbon dioxide
Reduction of nitrogen oxides to form harmless nitrogen gas
Oxidation of unburnt hydrocarbons to form carbon dioxide and water |
| As well as the cracking of alkenes, alkenes can also be made by: (2) | 1. Elimination of hydrogen halide from a halogenoalkane by heating with ethanolic sodium hydroxide
2. Dehydration of an alcohol by using a heated catalyst or a concentrated acid |
| What is dehydration | The elimination of water molecules from a reactant molecule |
| What is hydrogenation | The addition reaction of alkenes with hydrogen |
| Scientists in industry use the addition of steam to alkenes to make alcohols, how? | They react steam and the gaseous alkenes at a high temperature and pressure, in the presence of concentrated phosphoric acid, H₃PO₄, as the catalyst |
| What can be used to oxidis alkenes | Acidified potassium manganate(VII) solution |
| What is a polymer | Long-chain molecule made up of many repeating units |
| What are the small reactive molecules that react together to make the polymer called | monomers |
