4852752
Frage 1
Frage
How do you identify a carbonyl compound?
Antworten
-
Add Tollens' reagent
-
Add Biuret reagent
-
Add 2,4-DNPH
-
Add carboxylic acid
Frage 2
Frage
What is Brady's reagent?
Antworten
-
A mixture of H2SO4 and benzene + 2,4-DNPH
-
A mixture of HCl and ethanol + 2,4-DNPH
-
A mixture of NaOH and methanol + 2,4-DNPH
-
A mixture of H2SO4 and methanol + 2,4-DNPH
Frage 3
Frage
What's formed when 2,4-DNPH is added to an aldehyde/ketone?
Antworten
-
A blue solid
-
An orange/yellow precipiate
-
An orange/yellow solution
-
A green precipitate
Frage 4
Frage
What does the 2,4-DNPH derivative confirm?
Antworten
-
The presence of C=O
-
The presence of COOH
-
The presence of OH
-
The presence of COO
Frage 5
Frage
What happens when 2,4-DNPH added to carboxylic acid/ester?
Antworten
-
An orange/yellow precipitate formed
-
An orange to green colour change
-
A solid disappears
-
No precipitate formed
Frage 6
Frage
What is Tollen's reagent?
Antworten
-
A weak oxidising agent
-
A weak reducing agent
-
A strong oxidising agent
-
A strong reducing agent
Frage 7
Frage
What happens to aldehydes when Tollens' reagent is added to it?
Antworten
-
Oxidised to ketones
-
Reduced to carboxylic acids
-
Oxidised to carboxylic acids
-
Reduced to alcohols
Frage 8
Frage
What observation do you see when Tollen's reagent is added to an aldehyde?
Antworten
-
Brown precipitate
-
Silver mirror
-
No observation
-
Brick red precipitate
Frage 9
Frage
Why is a silver mirror formed?
Antworten
-
Al ions oxidised to Al metal
-
Silver ions reduced to silver metal
-
Silver ions oxidised to silver metal
-
Al ions reduced to Al metal
Frage 10
Frage
What is the equation for the silver mirror being formed?
Antworten
-
Ag-(aq) + e+ ---> Ag(s)
-
Ag+(aq) ---> Ag(s) + e-
-
Ag+(s) + e- ---> Ag(aq)
-
Ag+(aq) + e- ---> Ag(s)
Frage 11
Frage
What observation do you see when Tollen's added to ketone?
Antworten
-
No observation
-
Silver mirror
-
Deep blue solution
-
Orange to green colour change
Frage 12
Frage
What's the reason for no observation?
Antworten
-
The reaction is too slow
-
Ketones are not reduced by Tollens' reagent
-
Ketones are not oxidised by Tollens' reagent
-
Ketones are just dead
Frage 13
Frage
What's the oxidising species in Tollens' reagent?
Antworten
-
Ag(aq)
-
Br+(aq)
-
Ag(s)
-
Ag+(aq)
Frage 14
Frage
What conditions are required for these reactions?
Antworten
-
Warm
-
Reflux
-
conc H2SO4
-
Alkaline
Frage 15
Frage
Filter and [blank_start]recrystallise[blank_end] product. Measure [blank_start]melting point[blank_end] of purified product which is very [blank_start]high[blank_end]. Compare the melting point to a [blank_start]database[blank_end] or [blank_start]data table[blank_end] to identify the unknown product and therefore the [blank_start]original[blank_end] carbonyl compound.
Antworten
-
recrystallise
-
melting point
-
high
-
database
-
data table
-
original
Frage 16
Frage
Why does the yellow/orange solid have to be recrystallised?
Antworten
-
Because it needs to be crystallised again
-
Because its slightly impure
-
Because it's fun
-
Because it needs to be more solid
Frage 17
Frage
Why can't boiling points be used to distinguish between aldehydes and ketones?
Antworten
-
It's not possible to know all of the boiling points for every single one
-
It will all boil away
-
Some are very close together/similar
-
It's not accurate enough
Möchten Sie mit GoConqr kostenlos Ihre eigenen Quiz erstellen? eigenen Mehr erfahren.