Unknownn1.x
Badges: 8
Rep:
?
#1
Report Thread starter 2 weeks ago
#1
Describe suitable chemical tests, with observations, that would confirm the presence of the functional groups in F and G
0
reply
Unknownn1.x
Badges: 8
Rep:
?
#2
Report Thread starter 2 weeks ago
#2
(Original post by dayaaa.x)
Describe suitable chemical tests, with observations, that would confirm the presence of the functional groups in F and G
Name:  99C34675-10A7-4733-81E8-6D5941D8B23D.jpeg
Views: 5
Size:  62.9 KBName:  D8519F86-3418-437A-925C-D452F7F249BF.jpeg
Views: 8
Size:  69.3 KB
0
reply
EierVonSatan
Badges: 21
#3
Report 2 weeks ago
#3
What are the functional groups present in F and G?
0
reply
Unknownn1.x
Badges: 8
Rep:
?
#4
Report Thread starter 2 weeks ago
#4
(Original post by EierVonSatan)
What are the functional groups present in F and G?
Ketone aldehyde alkene and aromatic (benzene ring)?
0
reply
EierVonSatan
Badges: 21
#5
Report 2 weeks ago
#5
(Original post by dayaaa.x)
Ketone aldehyde alkene and aromatic (benzene ring)?
F has an aldehyde

G has a ketone and an alkene (kind of!) but it has no benzene ring.

Is there a test you know that can distinguish between an aldehyde and a ketone?
0
reply
Unknownn1.x
Badges: 8
Rep:
?
#6
Report Thread starter 2 weeks ago
#6
(Original post by EierVonSatan)
F has an aldehyde

G has a ketone and an alkene (kind of!) but it has no benzene ring.

Is there a test you know that can distinguish between an aldehyde and a ketone?
Tollens test

So do I not need to mention the alkene?
0
reply
Pyruvic Acid
Badges: 17
Rep:
?
#7
Report 2 weeks ago
#7
(Original post by dayaaa.x)
Tollens test

So do I not need to mention the alkene?
You could use bromine water to show that a molecule is unsaturated.
0
reply
EierVonSatan
Badges: 21
#8
Report 2 weeks ago
#8
(Original post by dayaaa.x)
Tollens test

So do I not need to mention the alkene?
Tollen's reagent would confirm the presence of an aldehyde. You need a positive test for the ketone and the alkene.
0
reply
Pyruvic Acid
Badges: 17
Rep:
?
#9
Report 2 weeks ago
#9
(Original post by EierVonSatan)
F has an aldehyde

G has a ketone and an alkene (kind of!) but it has no benzene ring.

Is there a test you know that can distinguish between an aldehyde and a ketone?
Wait aha what’s the kinda of part for the alkene?
0
reply
EierVonSatan
Badges: 21
#10
Report 2 weeks ago
#10
(Original post by KaziMahathir)
Wait aha what’s the kinda of part for the alkene?
The position of that C=C with the C=O is it's own type of functional group - called an enone - it doesn't react like a normal ketone or alkene.

A bit like how a caboxylic acid has a C=O and an O-H but it's nothing like a ketone or alcohol.

I'm going to assume an A-level question would treat the C=C and C=O as separate groups :yep:
1
reply
Unknownn1.x
Badges: 8
Rep:
?
#11
Report Thread starter 2 weeks ago
#11
(Original post by EierVonSatan)
Tollen's reagent would confirm the presence of an aldehyde. You need a positive test for the ketone and the alkene.
So for aldehyde it’d be the tollens test
for the ketone itd be a carbonyl test using 2,4-DNP??
and for alkene- bromine water test?
0
reply
Pyruvic Acid
Badges: 17
Rep:
?
#12
Report 2 weeks ago
#12
(Original post by EierVonSatan)
The position of that C=C with the C=O is it's own type of functional group - called an enone - it doesn't react like a normal ketone or alkene.

A bit like how a caboxylic acid has a C=O and an O-H but it's nothing like a ketone or alcohol.

I'm going to assume an A-level question would treat the C=C and C=O as separate groups :yep:
Ahh, I didn’t know that. Thanks!
0
reply
EierVonSatan
Badges: 21
#13
Report 2 weeks ago
#13
(Original post by dayaaa.x)
So for aldehyde it’d be the tollens test
for the ketone itd be a carbonyl test using 2,4-DNP??
and for alkene- bromine water test?
I would use 2,4-DNP on both to show the prescence of an aldehyde/ketone then use Tollens after. Yep, bromine water for G
0
reply
Mason_taylor16
Badges: 7
Rep:
?
#14
Report 1 week ago
#14
i wanna try DNP
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Which of these would you use to help with making uni decisions?

Webinars (73)
12.13%
Virtual campus tours/open days (146)
24.25%
Live streaming events (51)
8.47%
Online AMAs/guest lectures (55)
9.14%
A uni comparison tool (141)
23.42%
An in-person event when available (136)
22.59%

Watched Threads

View All