Fractional distillation of crude oil

Crude oil

Fossil fuel from deep under ground

How was crude oil formed?

1. Crude oil is formed from the remains of dead plants and animals, particularly plankton.

2. These organic remains were covered by mud and sand, and buried in the earth.

3. Over millions of years, these organic remains were compressed under a lot of heat and pressure.

4. The heat and pressure chemically changed the organic remains into crude oil.

finite resources

limited resources

Non renewable fuels

coal, oil, natural gas, nuclear

Fractional distillation of crude oil

-crude oil is heated until most has turned into gas which is passed into a fractionating column

-fractionating column is heated from the bottom so it's cooler at the top

-hot gases rise to regions at cooler temps to condense into liquid

Hydrocarbons with the longest chains

Have highest boiling points , thick viscous liquids

Quickly condense into liquid and drain out early on

Poor fuels

Shorter chain hydrocarbons

Lower boiling points so stay as a gas longer

Most flammable-best fuels

Some stay as a gas the whole time

Petrochemical

Substances made from crude oil

Can be used as lubricants

Cracking

The breaking down of long-chained saturated hydrocarbons to form a mixture of shorter-chained alkanes and alkenes by heating them

Catalytic cracking

1. vaporise hydrocarbon

2. pass over hot powered aluminium oxide catalyst

Steam cracking

1. vaporise hydrocarbon

2. mix with steam

3. heat to a very high temperature

Cracking long chain hydrocarbons

Long chain—>shorter chain+alkene

(Decane—->heltane+propene)

covalent bonding

results from the sharing of electron pairs between two atoms

Limitations of dot and cross diagrams

Do not show the 3D shape of a molecule

Limitations of ball and stick model

Fails at indicating the movement of electrons

Simple molecules

Weak IMF which are broken down during melting not bonds

IMF increases with size of molecules

Don't conduct electricity as no charged particles

Alkanes

Hydrocarbons that contain only single bonds

Saturated

Viscous, volatile, flammable

Displayed formula for alkanes

alkane functional group

C-C

Alkane general formula

CnH2n+2

Alkenes

double bonds

Unsaturated

Displayed formula for alkenes

alkene functional group

C=C

Alkene general formula

CnH2n

Test for alkenes with bromine water

Colour change from orange to colourless

Alcohols functional group

OH-

Alcohol general formula

CnH2n+1OH

Displayed formula for alcohol

carboxylic acid functional group

COOH

Carboxylic acids general formula

CnH2n+1COOH

Displayed formula for Carboxylic Acid

functional group

group of atoms within a molecule that interacts in predictable ways with other molecules

Hydrocarbons

Compounds composed of only carbon and hydrogen

Homologous series

A family of molecules which share the same general for,ular and functional group