Chemistry Unit 1 - Organic Chemistry

Fossil fuels

Formed from remains of dead organic matter over millions of years at high Temp./Pressure

Ex. of Fossil Fuels

Coal (s) = dirtiest

Crude oil (l) = petroleum

Natural gas (g) = cleanest

Issues with Fossil fuels

Carbon Dioxide Emissions

Non-renewable

Alternatives to fossil fuels

Renewable energy: wind, solar, hydroelectric

Nuclear E (no Carbon dioxide emissions)

Complete Combustion

Fossil Fuel (Hydrocarbon) + O2 ➡ CO2 + H2O

Incomplete Combustion

Insufficient O2, produces toxic CO (Carbon Monoxide)

Crude Oil

Mixture of Hydrocarbons called alkanes

Can be separated through fractional distillation

Fractional Distillation

Separating mixtures according to boiling point

Fractional Distillation of Crude Oil

Oil is heated in a heater to 400 Celsius, becoming vapour, and then sent through a fractionating column (attached to thermometer), where substances with high boiling points settle in lower levels while substances with low boiling points settle higher before condensing into individual substances.

Small Molecules

Low boiling point

Very volatile

Flows easily

Ignites easily

Large molecules

High boiling point

Not very volatile

Does not flow easily

Does not ignite easily

volatile

Evaporates easily

viscous

Thick and sticky

Refining

Purification of substances through physical separation

Refinery gas

Non-condensable gases

Organic compound prefix for one

Mono-

Organic compound prefix for two

Eth-

Organic compound prefix for three

Prop-

Organic compound prefix for four

But-

What do organic compounds form when in groups?

Families

Functional Group

Group of atoms that gives a family its particular reactivity

Homologous series

Family of similar compounds with similar compounds with similar chemical properties

Carbon forms x bonds

4

Hydrogen forms x bonds

1

Alkanes

Hydrocarbons

Only SINGLE C-C bonds

Suffix -ane

Alkanes General Formula

Cn H(2n+2)

Alkenes

Hydrocarbons

Contain a DOUBLE C-C Bond

Suffix -ene

Alkenes General Formula

Cn H(2n)

Alcohols

Suffix -ol

Functional Group: OH

Has to be bonded to C

Alcohols General Formula

CnH(2n+1)OH

How do you differentiate between the same organic compound when the double bond/OH is placed differently?

Number the carbon an write the number of the carbon where the thing is located in between pre and suffix

Eg. Butene (double bond at start)

But-1-ene

Carboxylic Acids

Suffix -oic acid

Functional Group COOH

They are weak acids

General Formula for Carboxylic Acids

CnH(2n+1)COOH

Alkane Reactions

• saturated (can’t fit any more bonds around the C)

• This makes them quite unreactive

• They do burn (combustion), releasing E

Alkenes Reactions

• unsaturated (when double bond breaks, more atoms can be added)

• Undergo addition reactions with H2, Br2, Hydrogen Halides and H20

Alkane + H2

ethene (C2H4) + H2 ➡ ethane (C2H6)

Alkane + Bromine Water (Br2)

ethene (C2H4) + Br2 ➡ 1,2 - dibromoethane (C2H4Br2)

Alkene + Hydrogen Halide (H + Hydrogen)

ethene (C2H4) + HCl ➡ chloroethane (C2H5CL)

Alkene + H20 (g)/Steam

ethene (C2H4) + H2O (g) ➡ Ethanol (C2H5OH)

Alkenes Polymerisation

Making plastics using Alkenes

Where do Alkenes come from?

Crude oil (Fractional Distillation at 400C) ➡ Alkanes (Cracking at 800C w Catalyst) ➡ Alkenes

Cracking

The process of turning larger Alkenes (not so useful) into smaller, more useful Alkenes

Thermal Decomposition at High T using a Catalyst