Organic Chemistry - Knowledge Organiser

Vocabulary flashcards covering fractional distillation, hydrocarbon properties, cracking, and the structure and reactions of alkenes from the organic chemistry knowledge organiser.

Fractional distillation

The process used to separate the many hydrocarbons in crude oil into fractions of molecules with a similar number of carbon atoms based on differences in boiling points.

Petrochemical feedstock fuels

Fuels produced from crude oil fractions, including petrol, diesel oil, kerosene, heavy fuel oil, and liquefied petroleum gases.

Petrochemical industry products

Useful materials produced from crude oil fractions, including solvents, lubricants, polymers, and detergents.

Hydrocarbon property trends

As hydrocarbon molecules get bigger, boiling point and viscosity increase, while flammability decreases.

Complete combustion of a hydrocarbon

A reaction that oxidises the carbon and hydrogen in hydrocarbon fuels, releasing energy and producing carbon dioxide and water ($2C_2H_6 + 7O_2 \rightarrow 4CO_2 + 6H_2O$).

Cracking

The breakdown of hydrocarbons into smaller, more useful molecules, producing alkanes and alkenes.

Catalytic cracking

A cracking method that requires a high temperature and a catalyst to break down hydrocarbons.

Steam cracking

A cracking method in which hydrocarbons are mixed with steam and heated to a very high temperature.

Bromine water test

A chemical test used for alkenes in which orange bromine water turns colourless upon reaction.

Alkenes

Hydrocarbons containing a double carbon-carbon bond ($C=C$ functional group) that are more reactive than alkanes and used to produce polymers.

General formula of alkenes

$$C_nH_{2n}$$

Unsaturated molecules

Molecules that contain a double carbon-carbon bond and have two fewer hydrogen atoms than the corresponding alkane with the same number of carbon atoms.

Combustion of alkenes

Combustion in air that tends to occur with smoky flames because of incomplete combustion.

Addition reactions of alkenes

Reactions in which atoms from hydrogen, water, or halogens add across the carbon-carbon double bond, converting it into a single carbon-carbon bond.

Functional group of alcohols

$$-OH$$