Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Chemistry Year 1 and Year 2 > chapter 26 > Flashcards

chapter 26 Flashcards

(66 cards)

Start Studying
1
Q

secondary alcohols are oxidized to? and under what conditions

A

ketones
refluxed under acidified conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

the oxidizing agent in the oxidization of secondary alcohols

A

potassium dichromate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

primary alcohols are oxidized to what, and under what conditions
oxidizing agent?

A

aldehydes
distilled under acidic conditions
potassium dichromate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

can tertiary alcohols be oxidised

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what group is present in the structure of both aldehydes and ketones

A

a carbonyl group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

the position of the carbonyl group in a ketone and aldehyde

A

in a ketone, the carbonyl group is joined to two different carbons in the chain, while in aldehydes, the carbonyl group is found at the end of the carbon chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

the ending of a molecular structure of an aldehyde

A

CHO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

aldehydes are oxidized to

A

carboxylic acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

conditions for the oxidization of aldehydes and the oxidizing agent

A

reflux under acidic conditions
potassium dichromate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

when an aldehyde is oxidized, there is a color change in the dichromate solution from

A

orange to green

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

do ketones undergo oxidization

A

nope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

why is the C=O bond polar

A

because of the difference in electronegativity values of O and C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

nucleophile

A

a electron donor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

aldehydes and ketones can be reduced to
the reducing agent for such reactions?

A

alcohols
sodium tetrahydridoborate (III) (NaBH4)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

in nucleophilic addition, the C=O pie bond breaks in a ……………. manner forming a …………….. charged intermediate

A

heterolytic
negatively

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

in nucleophilic addition, the hydride ion is provided by

A

the NaBH4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe what happens in nucleophilic addition

A

lone pair on the hydride ion is attracted and donated to the partially positive carbon atom of the C=O bond. This forms a dative covalent bond

in nucleophilic addition, the C=O pie bond breaks in a heterolytic manner forming a negatively charged intermediate

the oxygen atom in C-O bond in the intermediate donates a lone pair of electrons to a hydrogen atom in a water molecule.

An alcohol is formed as a result

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

an aldehyde reacts with hydrogen cyanide to form
under what conditions
where do we get the hydrogen cyanide from

A

a hydroxynitrile
acidic conditions
NaCN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

why is the reaction between an aldehyde and hydrogen cyanide important

A

it provides a way to extend the carbon chain length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

on which atom is the lone pair in CN on

A

on C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

brady’s reagent

A

a solution of 2,4-DNP dissolved in methanol and sulfuric acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

describe a test to identify a carbonyl group in either an aldehyde and a ketone

A

add a 5cm depth of a solution of 2,4-DNP to a clean test tube
add 3 drops of the unknown compound. leave to stand
a yellow/orange precipitate forms if there is a carbonyl group(aldehyde or ketone) present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

if no crystals form when brady’s reagent is added to a solution containing a ketone or an aldehyde

A

add more sulfuric acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

how do we identify whether a carbonyl group is exactly in a certain molecule

A

the precipitate formed after adding Brady’s reagent is filtrated
then it is recrystallized
the melting point is then measured and compared with known values

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
tollen's reagent
a solution of silver nitrate in aqueous ammonia
26
in the tollen's reagent, what acts as the oxidizing reagent
Silver ions
27
an aldehyde is oxidized to
a carboxylic acid
28
if an aldehyde is present in the tollen's reagent test, what happens
a silver mirror is formed
29
will the tollen's reagent be able to identify ketones and why
no, because ketones cannot be oxidized further
30
if there are two carboxylic acids in a compound, the name changes to the corresponding alkane, with a............ added at the end
dioic acid
31
carboxylic acids can form hydrogen bonds with two compounds, what are these
water and other carboxylic acids
32
name the factor that decreases the solubility of carboxylic acids
an increase in the number of atoms in the non polar carbon chain
33
what happens to the solubility of carboxylic acids as the acid group(COOH) increases
the solubility increases further
34
carboxylic acids with up to 4 carbon atoms are all soluble in water, true or false
true
35
are carboxylic acids strong acids?
no they are rather weak acids
36
products formed when carboxylic acids react with metals
salt and hydrogen gas
36
products formed when carboxylic acids react with metals
salt and hydrogen gas
37
carboxylic acids react with metal carbonates to form
salt, water and carbon dioxide
38
carboxylic acid derivatives
compounds that can be hydrolysed to form the parent carboxylic acid
39
in hydrolysis, which bond breaks in a carboxylic acid derivative
the single bond between the carbon in the acyl group and a different group
40
suffix for acyl chlorides
oyl chlorides
41
how are acyl chlorides prepared
by reacting carboxylic acids with thionyl chloride
42
molecular formula of thionyl chloride
SOCl2
43
what are the products formed from the reaction of carboxylic acids with thionyl chloride
an acyl chloride, Sulphur dioxide and HCl gas Both gases are toxic
44
acyl chlorides are very unreactive, true or false
false they are very reactive
45
acyl chlorides react by losing ....?
their chloride ion while retain the C=O bond
46
nucleophile
an electron pair donor
47
condensation reaction
a reaction in which two molecules react together to form a larger molecule with the elimination of a small molecule
48
acyl chlorides react with alcohols or phenols to form
an ester and HCl
49
acyl chlorides react with water to form
an carboxylic acid and HCl
50
why should the reaction between acyl chlorides and water be carried out under anhydrous conditions
because if not, the acyl chloride will react violently with water to form the carboxylic acid
51
acyl chlorides react with ammonia to form
Primary amide
52
acyl chlorides react with amines to form
a secondary amide
53
how are acid anhydrides formed
from the condensation reaction between two molecules of carboxylic acid
54
which is more reactive, an acyl chloride, or an acid anhydride
acyl chlorides therefore acid anhydrides are more likely to be used in lab preparations while acyl chlorides might be too reactive
55
acid anhydrides react with alcohols to form
an ester and a carboxylic acid
56
functional group of esters
RCOOR R stands for a carbon group
57
esters are named from backwards to forwards, true or false
true
58
esterification
the reaction of a carboxylic acid with an alcohol to form an ester and water
59
can carboxylic acids react with phenols to form esters
no they cannot, because they are not reactive enough to do so. instead acyl chlorides and acid anhydrides are used
60
do esters react with acyl chlorides
no
61
acid hydrolysis of esters is the reverse of
esterification
62
in acid hydrolysis, the ester is heated under .................. with ..........................
reflux dilute aqueous acid
63
in acid hydrolysis, the ester reacts slowly with water. but the reaction is sped up by ........................ what acts as the catalyst
catalysis the dilute aqueous acid
64
alkaline hydrolysis is also known as
saponification
65
in alkaline hydrolysis, the ester is heated under............... with .................. to form a ......................... and an ...................
reflux aqueous hydroxide ions carboxylate ion alcohol

Chemistry Year 1 and Year 2 (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions