Topic C7- Organic Chemistry Flashcards
What is the formula for alkanes?
CnH2n+2
What is a homologous series?
A group of organic compounds that react in a similar way
What are saturated compounds?
Each carbon atom forms four single covalent bonds
What are the first four alkanes?
Methane, Ethane, propane and butane
Do hydrocarbons with shorter carbon chains have a higher boiling point or a lower boiling point?
Lower boiling point
What is the complete combustion of any hydrocarbon in oxygen formula?
Hydrocarbon + oxygen → Carbon dioxide + water
what is crude oil?
A fossil fuel formed from the remains of plants and animals, mainly plankton, that died millions of years ago and were buried in mud. over millions of years with high temperature and pressure the remains turn to crude oil
What are finite resources and an example?
Resources that will run out one day
Fossil Fuels
How does fractional distillation separate compounds in crude oil?
1) The oil is heated until most of it has turned into gas. The gases enter a fractionating column that has a temperature gradient.
2) Longer hydrocarbons have high boiling points. They condense back into liquids when they’re near the bottom.
3) The shorter hydrocarbons have lower boiling points. They condense near to the top of the column, where it’s cooler.
What does cracking do to long-chain hydrocarbons?
The longer alkane molecules produced from fractional distillation are turned into smaller, more useful ones
What is the test for alkenes?
Bromine water is mixed into a solution, if alkenes are present the colour will change from orange to colourless
What is one method of cracking?
Vaporise the hydrocarbons, mix them with steam and then heat them to a very high temperature. This is known as steam cracking.
