The Student Room Group
Reply 1
Oh and what are the precipitates being formed?
Maybe the halogen (Br/Cl/I) atoms take the place of the hydrogens in cyclohexane? Couldn't be sure though...
Reply 3
In cyclohexane, iodine is purple, bromine is a strong orange/yellow and chlorine is pale yellow.
Reply 4
I just copied it from the book *shrug*.
Reply 5
It would have to be in the presence of UV light surely... free radical substitution? I don't know if this is possible or not, as cyclohexane is very inert. Only really reacts with Superacids like Fluoroantimonic Acid.

If substitution can occur, which I doubt, then:

C6H12 + Cl2 -> C6H11Cl + HCl

Further substitution would occur, leading to C6H6C6 eventually:

C6H12 + 6Cl2 -> C6H6Cl6 + 6HCl

Same reactions with Br2 and I2.

I can repost with initiation, propogation and termination if you like. But bear in mind that this would only occur in quite harsh conditions (eg very hot, high intensity UV light)...
Reply 6
[QUOTE]
well yeh they're pretty much the same as what i said. meh.[/QUOTE
:laughing: fair enough. :smile:
Reply 7
Halogens don't react with cyclohexane (not at room temperature anyway), they only mix with it. If you add cyclohexane to chlorine/bromine water or iodine solution and shake it, the halogen dissolves in the cyclohexane layer because the halogen and the cyclohexane have the same intermolecular forces (instantaneous dipole-induced dipole).
Reply 8
Im so confused, we just mixed together halogens in water and in cyclohexane and we have to include the equations for it in a presentation we have to make.
Reply 9
so what is the precipitate? I'm going to fail chemistry!
we just mixed together halogens in water and in cyclohexane.

And? What did you see?
Reply 11
Chlroine water had like a white top layer, Bromine had a dar yellow top layer and Iodine just went reddy/brown
Reply 12
i dont know what to do becuase my results are well out what they are supposed to be but everyone else in my class got the same.
Reply 13
I've done the same thing (if you're doing salters). Mixing chlorine/bromine/iodine water simply shows that halogens are more soluble in cyclohexane than in water, there is not a reaction.
Reply 14
Original post by Chrrams
It would have to be in the presence of UV light surely... free radical substitution? I don't know if this is possible or not, as cyclohexane is very inert. Only really reacts with Superacids like Fluoroantimonic Acid.

If substitution can occur, which I doubt, then:

C6H12 + Cl2 -> C6H11Cl + HCl

Further substitution would occur, leading to C6H6C6 eventually:

C6H12 + 6Cl2 -> C6H6Cl6 + 6HCl

Same reactions with Br2 and I2.

I can repost with initiation, propogation and termination if you like. But bear in mind that this would only occur in quite harsh conditions (eg very hot, high intensity UV light)...



two layers form when a halogen and cyclohexane react
what actually is the bottom layer?
reply asap please, my salters isa is tomorrow :l
Original post by amaranthine
Anybody help with wat the eqautions are for Bromine/Chlorine/Iodine water with cyclohexane? It's much appriciated!

Sorry for the late reply. Anynway in cyclohexane, Chlorine is pale-green, bromine is orange, iodine is violet
we did that exact experiment today with the halogens and cyclohexane with water and then writing up the powerpoint for the OCR B salters course - although i have no idea what is supposed to go in it -.-
Reply 17
Sorry amaranthine, I hope it's not too late. But I actually have no idea
Original post by JamFlan
Sorry amaranthine, I hope it's not too late. But I actually have no idea


It's actually quite too late. You are 9 years late