♥Samantha♥
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I need to describe experiments to identify unlabelled bottles of the following substances:
butan-2-ol
2-methylpropan-2-ol
butan-1-ol
pent-1-ene
3-iodopropan-1-ol

Okay so I have some ideas, as all of these are either alcohols or alkenes I could start by doing a bromine water test or PCl5 test to separate the groups. Then for the alcohols I could do tests for primary, secondary and tertiary. But after that I don't know how I would differentiate between butan-1-ol and 3-iodopropan-1-ol, both primary alcohols, and between pent-1-ene and 3-chloroprop-1-ene, both alkenes. I'm guessing it's to do with the halogen atoms, but I don't know how I could do the silver nitrate test as there aren't halide ions in solution, they are covalently bonded. I know that for haloalkanes, adding NaOH solution releases the halide ions into solution, but I don't think that works for haloalcohols or haloalkenes.

Can someone help? Or suggest I completely different method for identifying the substances, maybe I've been going down the wrong path.

tl;dr: I need a test to differentiate haloalcohols from normal alcohols and haloalkenes from normal alkenes.
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♥Samantha♥
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could i hydrogenate the alkenes to alkanes then do the test?
what about alcohol, could i eliminate to alkene then hydrogenate to alkane?

seems like too many steps :/
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manwtfisthis
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Adding silver nitrate solution causes a substitution reaction to happen which replaces the halogen with -OH. The products include a halide ion, which will then form a Silver Halide precipitate.

The same mechanism is used in testing the speeds of hydrolysis of haloalkanes.

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charco
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(Original post by ♥Samantha♥)
I need to describe experiments to identify unlabelled bottles of the following substances:
butan-2-ol
2-methylpropan-2-ol
butan-1-ol
pent-1-ene
3-iodopropan-1-ol

Okay so I have some ideas, as all of these are either alcohols or alkenes I could start by doing a bromine water test or PCl5 test to separate the groups. Then for the alcohols I could do tests for primary, secondary and tertiary. But after that I don't know how I would differentiate between butan-1-ol and 3-iodopropan-1-ol, both primary alcohols, and between pent-1-ene and 3-chloroprop-1-ene, both alkenes. I'm guessing it's to do with the halogen atoms, but I don't know how I could do the silver nitrate test as there aren't halide ions in solution, they are covalently bonded. I know that for haloalkanes, adding NaOH solution releases the halide ions into solution, but I don't think that works for haloalcohols or haloalkenes.

Can someone help? Or suggest I completely different method for identifying the substances, maybe I've been going down the wrong path.

tl;dr: I need a test to differentiate haloalcohols from normal alcohols and haloalkenes from normal alkenes.
I think that you are correct with using NaOH to bring the halide ion into solution with subsequent addition of silver ions. It will work with primary haloalkanes and should not be affected by the alcohol group or the alkenyl group.

For differentiation you could always use microscale boiling point (Siwolobov).
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Pigster
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Adding NaOH then AgNO3 will make the silver ions precipitate as Ag2O.

Like Charco said, just add the AgNO3 (in ethanol solvent) and you'll get a ppt.
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♥Samantha♥
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(Original post by charco)
I think that you are correct with using NaOH to bring the halide ion into solution with subsequent addition of silver ions. It will work with primary haloalkanes and should not be affected by the alcohol group or the alkenyl group.

For differentiation you could always use microscale boiling point (Siwolobov).
ok thank you!
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