Chemistry IR spectroscopy IAS question.

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Roha125
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This from new IAS specimen paper of Chemistry Unit 3.
I have problem in 3.e.i.
The answer is 'C-H of aldehyde'.Can anyone help,how will i get to that answer.
Will IAS unit 3 give us extra data booklet for IR wavelength values.
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Pigster
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(Original post by Roha125)
I have problem in 3.e.i.
The answer is 'C-H of aldehyde'.Can anyone help,how will i get to that answer.
Will IAS unit 3 give us extra data booklet for IR wavelength values.
Hopefully, you'd worked out that it was an alcohol to start with, i.e. propan-1-ol or -2-ol.
Distilled with acidified dichromate would produce propanal or propanone (respectively).
The peak stated is only present in aldehydes.

You must Shirley be given the data booklet of IR values.

And don't call me surely.
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CuriosityYay
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(Original post by Pigster)
And don't call me surely.
What does that mean?
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Pigster
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(Original post by CuriosityYay)
What does that mean?
You've not seen Airplane! ?
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Roha125
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No IR data wasn't give.the specimen doesn't have it.

Could it be that we used distillation technique and it is only used for aldehyde.Ketone has no effect of reflux or distillation.Still in doubt with my theory
(Original post by Pigster)
Hopefully, you'd worked out that it was an alcohol to start with, i.e. propan-1-ol or -2-ol.
Distilled with acidified dichromate would produce propanal or propanone (respectively).
The peak stated is only present in aldehydes.

You must Shirley be given the data booklet of IR values.

And don't call me surely.
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CuriosityYay
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(Original post by Pigster)
You've not seen Airplane! ?
Airplane! 1980 movie, no didn't see it.

So it is just a movie reference, fair enough.
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Pigster
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(Original post by Roha125)
No IR data wasn't give.the specimen doesn't have it.

Could it be that we used distillation technique and it is only used for aldehyde.Ketone has no effect of reflux or distillation.Still in doubt with my theory
It'll say somewhere in your spec whether (but I'll bet that) you get a datasheet.
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Ailurophile03
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this is the specimen paper right?
i also wrote aldehyde, this is because previously they told me to that (the alcohol has been distillated) and we know when we distill an alcholol we get aldehyde
(Original post by Roha125)
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This from new IAS specimen paper of Chemistry Unit 3.
I have problem in 3.e.i.
The answer is 'C-H of aldehyde'.Can anyone help,how will i get to that answer.
Will IAS unit 3 give us extra data booklet for IR wavelength values.
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Pigster
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(Original post by Ailurophile03)
this is the specimen paper right?
i also wrote aldehyde, this is because previously they told me to that (the alcohol has been distillated) and we know when we distill an alcholol we get aldehyde
This isn't quite right.

If you have a primary alcohol, it can be converted into either an aldehyde (using distillation) or a carboxylic acid (using reflux).

A secondary alcohol can only be converted into a ketone using either distillation or reflux, so you might as well use reflux as it will have a faster rate.
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Ailurophile03
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(Original post by Pigster)
This isn't quite right.

If you have a primary alcohol, it can be converted into either an aldehyde (using distillation) or a carboxylic acid (using reflux).

A secondary alcohol can only be converted into a ketone using either distillation or reflux, so you might as well use reflux as it will have a faster rate.
ur right,
but i dont think we have ketones in our spec ( at least i never came across)
we need to know how to make aldehydes and carboxylic acid.
that is why i assumed the aldehyde thing
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Roha125
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And the question d.ii. we were told to draw isomers of which one was a ketone
(Original post by Ailurophile03)
ur right,
but i dont think we have ketones in our spec ( at least i never came across)
we need to know how to make aldehydes and carboxylic acid.
that is why i assumed the aldehyde thing
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Ailurophile03
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okay thn i have no idea
(Original post by Roha125)
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Size:  91.3 KB sorry but ketone is in our specs.
And the question d.ii. we were told to draw isomers of which one was a ketone
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Ailurophile03
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just checked the edexcel website, they only give data booklet book or unit 2,4,5
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Roha125
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a sigh of relief

(Original post by Ailurophile03)
just checked the edexcel website, they only give data booklet book or unit 2,4,5
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Ailurophile03
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that explains it all, i was kinda worried!
thankss
(Original post by Roha125)
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a sigh of relief
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