Bromine Water Prac (1 Viewer)

[study1234]

What are the equations for bromine water with cyclohexene and cyclohexane (with UV light)? I've searched around, but I've got a variety of answers

 

[golgo13]

I think and think i use, it's just the same as the start but you just state the colour change LOL

 

[DamTameNaken]

Cyclohexene with bromine water:
C6H10 + Br2 ----> C6H10Br2

Cyclohexane with Bromine water:
C6H12 + Br2 ----> C6H12 + Br2 i.e No reaction

Cyclohexane with Bromine water in UV light:
C6H12 + Br2 ----> C6H11Br + HBr

 

[DamTameNaken]

The reason you got a variety of answers is probably because people classify Bromine water as several different substances e.g. Br2, HBr HOBr

there is an obvious explanation for this as the equilibrium reaction for Water and Bromine is something like: Br2 + H2O <--> HBr + HOBr.

The reason why most textbooks use Br2 is because the equilibrium reaction heavily favours the left in standard lab conditions (1 atmosphere, 25 degrees celsius).

You can use HBr in the HSC but Br2 is allowed and probably more correct (and probably easier to remember too).

 

[madharris]

Cyclohexene with bromine water:
C6H10 + Br2 ----> C6H10Br2

Cyclohexane with Bromine water:
C6H12 + Br2 ----> C6H12 + Br2 i.e No reaction

Cyclohexane with Bromine water in UV light:
C6H12 + Br2 ----> C6H11Br + HBr

Bromine water is actually BrOH as shown in:
Br2 + H2O --> BrOH + HBr

This means that the hexene and bromine water reaction is
C6H10 + BrOH --> C6H10BrOH

However in saying that, when I asked one of the teachers at my school (who is an hsc marker), he said that because Br2 is commonly taught and is easy to understand, the will accept Bromine water as both BrOH and Br2 (both aqueous of course)

EDIT: found this, go to mitochonria's explanation http://community.boredofstudies.org/showthread.php?t=234351

 

[study1234]

Thanks guys Also, for the products (C6H10Br2 & C6H11Br & HBr) when you add bromine water, are they liquids or aqueous (since bromine water is aqueous)?