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Chemistry P3 7/6/2010

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J.Darren:
Organic Chemistry

Fuels :

- Coal
- Natural gas (Methane)
- Petroleum (Crude oil)

Fractional distillation:

N/A - Refinery gas (used as a fuel)
30 degree celsius - Gasoline (used as a fuel in cars)
110 degree celsius - Naphtha (used as make chemicals)
180 degree celsius - Kerosene / Paraffin (used as a fuel in jet engines)
260 degree celsius - Diesel oil / Gas oil (used as a fuel in diesel engines)
N/A - Fuel oil (used as a fuel for ships and for home heating systems)
N/A - Lubricating oil (used in waxes and polishes)
N/A - Bitumen (used as a fuel in jet engines)

Homologus series :

- Trend in physical properties
- Same general formula
- Same functional group
- Similar chemical properties
- Differs from its neighbouring member by CH2

Properties of Alkanes :

Saturated hydrocarbons
General formula : CnH(2n+2)
Increase in boiling point
Physical state at room temperature : Gas > Liquid > Solid

Combustion of alkanes :

Gives CO2 and water, incomplete combustion will give CO and water.

Subsitution reaction :

Condition - Bright light (Photochemical)

Alkanes react with chlorine to give a mixture of chloroalkanes. One hydrogen atom is subsituted by one chlorine atom.

Methane + Chlorine -> Chloromethane (CH3Cl) + HCl

J.Darren:
Properties of Alkenes :

Unaturated hydrocarbons
General formula : CnH2n

Alkenes are made by cracking alkanes. Long alkene molecules are passed over a heated catalyst consisting of Silicon (IV) Oxide and Aluminium Oxide.

C10H22 -> C8H18 + C2H4

Decane -> Octane + Ethene

Hydrogen can also be made by cracking :

C10H22 -> C7H14 + C3H6 + H2

Decane -> Alkene + Alkene + Hydrogen

Cracking is used to make :

- Alkenes
- Hydrogen
- Petrol from higher fractions

Addition Reaction :

Hydrogenation

Condition - 180 degree celsius, Nickel catalyst

Alkene + Hydrogen -> Alkane

Hydration

Condition - 300 degree celsius, Phosphoric Acid, 60 atmospheric pressure

Alkene + Water -> Alcohol

Test for an alkene

When a few drops of Bromine water are added to a tube of ethene gas, the colour changes from brown to colourless.

Ethene + Bromine -> Dibromoethane

6394:
lol u started
i ws thinkin of starting it 2day
By the way i wil pm u de useful ntes n tricks i hav
!!!!
:P

princess12:
thanxs a good information

WARRIOR:
i was gonna start mine 2mrw :(

i guess u go on with this :/ ill make another

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