3.8 I can describe the reaction between alkenes and bromine

1.       Write the word equation showing the reaction between ethene and bromine water

Ethene + Bromine (l) --> bromoethane + hydrogenbromide 

                                         or dibromoethane 

2.       Draw the displayed formula of the reaction above

3.       Explain the observations

The liquid turns from brown/ yellow to colourless because the bromine molecules are separated and loses it's colour

4.       Why does this reaction not need a catalyst?

 A catalyst is not needed because alkenes and the carbon carbon double bond is very reactive.

5.       What type of reaction is this called?

This is called an addition reaction

6.       Explain why this reaction is useful

 Because it shows when a non saturated bond is present

3.2 and 3.3 I can recall the general formula and displayed formula of alkanes

 

What is the General formula of Alkanes?     C_nH_2n+2

 _{Describe the Trend in Boiling Points:} : A straight-chain alkane will have a boiling point higher than a branched-chain alkane due to the greater surface area in contact with the heat source, also, as the mass of the alkane increase the boiling point increases

Draw the displayed formula of the three isomers of pentane:

 

3.1 I can explain the terms homologous series, hydrocarbon, saturated, unsaturated, general formula and isomerism

Term	Definition	Example
Homologous series	A family or series of Hydrocarbons that have similar chemical properties.	Alkanes Alkenes
Hydrocarbon	Organic compounds that consist of only Hydrogen and Carbon	Ethanol
Saturated hydrocarbon	Alkanes (paraffins) - hydrocarbons that have a carbon 'skeleton' or 'back-bone'  Hydrogen must have 4 bonds	Methane
Unsaturated hydrocarbon	Alkenes (olefins) - Hydrocarbons with at least one carbon to carbon double bond.	Ethylene
General formula	Within a series; it shows the relationship between the number of C atoms and H atoms in the compounds Alkanes - CnH2n+2  Alkenes - CnH2n.	Hexane C6H14 Propene C3H6
Isomerism	Isomers have the same formula but their atoms are arranged differently.  Different physical properties	Propane