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Edexcel 6CH07/01- May 8th 2013 - AS Chemistry Unit 3B

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Yes its there BUT NOT with Tollens or fehlings reagents. This might be an accepted alternative.
But
You could distinguish by a refluxing with acidified Potassium Di Chromate (or manganate if you take necessary precautions). Colourchange will only show up for aldehyde.
Tollens solution or fehling is also good but out of the spec.

Similarly distinguishing between carboxylic and aldehyde or ketone can be done by litmus.

I dont know. where in the spec is Tollens reagent and Fehling's mentioned????

I suppose your right. I didn't check the spec, but my tutor taught it, so I assumed it was in the spec...

Hope we don't get something new like that :s-smilie:

Reply 101

RoyalBlue7

Carbonyl compounds are with C to O double bond as in ketone aldehyde and carboxylics acid. The Fehling's and Tollen's is in A2. Maybe Thilak :biggrin:

would have added it.

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(edited 10 years ago)

Reply 102

Relaxedexams

Original post by StUdEnTIGCSE

Carbonyl compounds are with C to O double bond as in ketone aldehyde and carboxylics acid. The Fehling's and Tollen's is in A2. Maybe Thilak :biggrin:

would have added it. Here

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Haha, he always teaches extra and finishes syllabus slowly :tongue:

Reply 103

Relaxedexams

Original post by StUdEnTIGCSE

How to investigate the solubility of simple molecules in different solvents?

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Is this in the spec? :eek:

How do you measure solubility? increase in volume? (very doubtful)

Reply 104

DanielDaniels

Original post by Relaxedexams

Is this in the spec? :eek:

How do you measure solubility? increase in volume? (very doubtful)

man please help me in the questions i sent

Reply 105

Relaxedexams

Original post by Daniel Atieh

pleeeeassse help me in Jun 2009 q 1 (aiv) and b(v)....didnt get AT ALL!!! http://www.edexcel.com/migrationdocuments/QP%20GCE%20Curriculum%202000/June%202009/6CH07_01_que_20090515.pdf

1 (a) (iv)

White ppt is formed, the new substance is Magnesium Hydroxide. (I did this in class, not sure if its in the syllabus.)

(b) (v)

The sulfur in H2SO4 is reduced to Sulfur dioxide. Bromine in HBr is oxidised to Br2.

Reply 106

DanielDaniels

Original post by Relaxedexams

also for q 2 part ai - why we hv to draw the line at 3.5 mins? is it cauz at the mid?

Reply 107

Relaxedexams

Original post by StUdEnTIGCSE

Carbonyl compounds are with C to O double bond as in ketone aldehyde and carboxylics acid. The Fehling's and Tollen's is in A2. Maybe Thilak :biggrin:

would have added it.

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In simple distillation, the 'receiving end of the flask' is the end at the conical flask right?