3.5 I can recall the reaction of methane and bromine

1. Alkanes react with bromine in the presence of ultra violet light.

2. Explain why this condition is necessary.

The UV is the essential energy required in order for the chemical reaction to happen.  

3. What is this type of reaction called = Substitution Reaction.

4. State and explain the observations = Brown gas turns colourless because the bromine as a reactant is brown and the products bromomethane and hydrogen bromide is colourless

5. Draw the displayed formula of the reaction between methane and bromine (upload a photo)

6. Write out a balanced (with state symbols) the reaction between ethane and chlorine

C2H6 (g) + Cl2 (g) --> C2H5CL (g) + HCl (g)

7. State and explain the observations in this chemical reaction

Yellow Gas turns Colourless because the chlorine as a reactant is yellow and the products chloroethane
 and hydrogen chloride is colourless