3.8 Describe the addition reaction of alkenes with bromine, including decolourising of bromine water as a test for alkenes

Create blog post titled '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 water -----> bromoethane + hydrogenbromide

2.       Draw the displayed formula of the reaction above

Take a photo of the answers to 1. and 2. and upload to your blog

3.       Explain the observations: 

4.       Why does this reaction not need a catalyst? Because alkenes are highly reactive.

5.       What type of reaction is this called? Addition reaction

6.       Explain why this reaction is useful: 

3.5 Recall the reaction of methane with bromine to form bromomethane in the presence UV light

Alkanes react with bromine in the presence of: UV Light. 

Explain why this condition is necessary: the UV light is the source of energy needed to break the weak inter molecular forces in between molecules.

  What is this type of reaction called: substitution reaction 

 State and explain the observations: Alkanes are colourless and bromine is brownish orange, when the reactants are given energy to break inter molecular bonds the bromine is less saturated and the product therefor turns colourless 

Write out a balanced (with state symbols) the reaction between ethane and chlorine: C₂H₆ + Cl₂ à C₂H₅ + HCl

 State and explain the observations in this chemical reaction: The chlorine starts as a green/yellow gas. When it reacts the chlorine is less saturated and the product is more saturated making the product colourless

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

5.11 I can recall how nitrogen oxides are formed in car engines

a.       Write the general equation for the combustion of a fuel. Fuel + oxygen -----> energy + oxides

b.      During combustion the nitrogen in air can react to form what gases? NOx gases

c.       What condition is necessary for the formation of these gases? High temperature

d.      In what common object is this condition found? Cars

e.      Why is this condition needed for nitrogen to react? Nitrogen molecules are diatomic and have triple covalent bonds 

f.        What are the dangers of the products from this reaction? Cancer, Lung disease, 

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

Term	Definition	Example
Homologous series	Organic compounds with a similar general formula	Alkane
Hydrocarbon	A compound of hydrogen and carbon	Alkene, alkanes
Saturated hydrocarbon	A hydrocarbon formed with simple bonds	Alkanes
Unsaturated hydrocarbon	A hydrocarbon with one double or triple bond	Alkenes
General formula	A formula to show the mathematical relations between a carbon and hydrogen	CnH2n+2
Isomerism	Compounds with the same molecular formula but different structural formulas	2,2 Dimethylpropane

petroleum gas

fuel oil