Use of cyclohexene/cyclohexane? (1 Viewer)

[danif]

Why do we use cyclohexene/cyclohexane instead of just hexene and hexane for the "Bromine" experiment? is it because they're less volatile?
ta
-dani

 

[LSP]

they exist in liquid form at room temperature and pressure unlike methane, ethane exist in gas

 

[omg_a]

^yup. dont foget when writing the formula of say cyclohexene it is C6H10 not H12.

 

[Slidey]

Why H10?

It's not cyclohexyne.

And furthermore, we use cyclohex- because unlike normal hex- it is liquid at room temperature and non-volatile.

EDIT: Nevermind. Since it's a ring, obviously ends meet, so CH3 to CH3, but since these two ends are already full, we need to drop 2 hydrogen.

 

[LSP]

cyclohexene C6H12
cyclohexane C6H14

im wrong then, but lucky me...thanx guys

 

[Slidey]

No, it IS C6H10:

http://environmentalchemistry.com/yogi/chemicals/formula/C6H10.html

 

[tina_goes_doo]

Ok. Say the question goes state the name of the alkene you would use. If you put down something like ethene even though you didn't use it, would you still get the mark?

 

[Xayma]

Cyclohexane C₆H₁₂
Cyclohexene C₆H₁₀

 

[CM_Tutor]

Ok. Say the question goes state the name of the alkene you would use. If you put down something like ethene even though you didn't use it, would you still get the mark?

No - the examiner's report from 2002 makes this point quite clearly.

 

[CM_Tutor]

Danif, cyclohexane and cyclohexene are used rather than hexane and a hexene for safety reasons - hexane is markedly more toxic than cyclohexane.

and Xayma is correct about the formulae.

 

[Jazz Man Tim]

hehe our chem class used both cyclohexane(ene) and hexane(ene)...

 

[Casmira]

same here, i think it was saturated that discoloured the bromine

 

[mervvyn]

same here, i think it was saturated that discoloured the bromine

nup, other way around. The unsaturated hydrocarbon (-ene) would discolour the bromine water almost instantly on shaking with it, the saturated one (-ane) would need 5 min or so of sunlight (for the UV).