Hydrocarbon + Bromine + Sulfuric acid

[darkheavens]

Ok, so in this practical that we had to complete, in one part of it, we had to mix a hydrocarbon (C6H10 and C6H12) with sulfuric acid, and then add bromine to it - this was done in two test tubes, one hydrocarbon in each.

Then we had to answer the question: "Suggest why bromine is used to test whether the hydrocarbon is saturated or unsaturated"

Anyone able to answer this?

[appianway]

Bromine's brown. If the hydrocarbon is unsaturated, the double bond(s) will break and the bromine will bond to the hydrocarbon and thus appear clear.

[darkheavens]

So what does the sulfuric acid do? Nothing?

[Twenty10]

NOt 100% sure but it was probably used as a catalyst.

[m@tty]

Isn't it a catalyst?

[Mao]

No idea why there was sulfuric acid there, but bromination (or halogen addition reaction) generally don't need a catalyst. The only case when bromination is needed to be acid catalysed is when a carbonyl is brominated..

Can you elaborate more on your experimental procedure?

[darkheavens]

Test tube 1:
We put 10 drops of C6H10. Then 2 drops of bromine. Then 1 drop of sulfuric acid and observed what happened to the colour of the solution

Test tube 2:
Repeated above, except with C6H12 instead of C6H10.

[Studyinghard]

Doesnt the reaction take some time to happen so in the class condition you want to quicken the process by adding a catalyst?

[crayolé]

Doesnt the reaction take some time to happen so in the class condition you want to quicken the process by adding a catalyst?

Yeah but usually you dont need a catalyst for halogenation

[Martoman]

No idea why there was sulfuric acid there, but bromination (or halogen addition reaction) generally don't need a catalyst. The only case when bromination is needed to be acid catalysed is when a carbonyl is brominated..

Can you elaborate more on your experimental procedure?

I concur. Its just a distracter.