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unit 2 2011 june help

2-chlorobutane reacts with alcoholic potassium hydroxide at a high temp to for a mixture of gaseous alkanes. draw a fully labelled diagram of the appartus you would use to prepare and collect this mixture...

can someone please explain and draw what is wanted i dont understand... why does it reject distillstion and reflux ..
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Original post by pondsteps
2-chlorobutane reacts with alcoholic potassium hydroxide at a high temp to for a mixture of gaseous alkanes. draw a fully labelled diagram of the appartus you would use to prepare and collect this mixture...

can someone please explain and draw what is wanted i dont understand... why does it reject distillstion and reflux ..


Because you are told that it is a mixture of gaseous alkenes. They would all escape if you used reflux or distillation apparatus!
Original post by charco
Because you are told that it is a mixture of gaseous alkenes. They would all escape if you used reflux or distillation apparatus!

but the question said how could you collect the mixture....
Original post by pondsteps
but the question said how could you collect the mixture....


So you have to lead the gases through gas-tight apparatus into a vessel under water (for examples)
Original post by charco
So you have to lead the gases through gas-tight apparatus into a vessel under water (for examples)


ohh okay so when gaseous products are given off we cannot use use distillation and reflux to collect the product?
Original post by pondsteps
ohh okay so when gaseous products are given off we cannot use use distillation and reflux to collect the product?


gases are gases!

They diffuse, expand and spread out to fill all available volume. You have to restrict the volume and collect them in some way.
Original post by charco
gases are gases!

They diffuse, expand and spread out to fill all available volume. You have to restrict the volume and collect them in some way.


so to collect gases i have to use a gas syringe or over water right
Original post by pondsteps
so to collect gases i have to use a gas syringe or over water right


yup

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