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Flashcards in Carbonyl compounds Deck (32)
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1
Q

What is a carbonyl group?

A

A carbon-oxygen double bond

2
Q

What compounds is a cabonyl group found in?

A

Aldehyde and ketones

3
Q

What is the relative charge o the carbon of a carbonyl group?

A

+

4
Q

What feature of a carbonyl group makes it susceptible to attack from nucleophiles?

A

The polarity of the double bond.

5
Q

What are the typical reactions of carbonyl compounds?

A

Nucleophilic addition

6
Q

What happens ina nucleophilic addition reaction?

A

The nucleophile adds onto the C^d+ and a hydrogen adds on to the O^d-

7
Q

What are the products called when the nucleophile was a cyanide ion?

A

Hydroxynitriles.

8
Q

What can aldehydes be oxidised into and what is the oxidising agent?

A

Carboxylic acids, acidified potassium dichromate

9
Q

What can aldehydes be reduced into and what is the reducing agent?

A

Primary alcohols, Sodium tetrehydridoborate(III) NaBH4

10
Q

What can ketones be reduced to?

A

Secondary alcohols.

11
Q

What happens when an aldehyde is warmed with Tollen’s reagent?

A

Ag+ is reduced to Ag

12
Q

What happens when an aldehyde is is warmed with Fehling’s solution?

A

The Cu2+ ions are reduced to Cu+

13
Q

What is the general formula of a carboxylic acid?

A

R-COOH

14
Q

What is the general formula of an ester?

A

R-COO-R

15
Q

How do you name an ester?

A

The name of the second R group is placed first and then the first R group with -oate on the end.

16
Q

Why is the carbonyl group in carboxylic acids more polar than the carbonyl group in aldehydes and ketones?

A

Due to the second oxygen atom bonded to it.

17
Q

What is the name for the ion produced if the H^d+ is lost from a carboxylic acid and what happens to the charge?

A

A carboxylate ion, the negative charge is spread over three atoms.

18
Q

Why is a carboxylate ion stable?

A

Due to the delocalised electrons

19
Q

What is produced when ethanoic acid reacts with sodium hydrogencarbonate?

A

Sodium ethanoate, CO2 and H2O

20
Q

How are esters produced and what is the name of the reaction?

A

Carboxylic acids reacting with alcohols with a strong acid catalyst (H2SO4).

21
Q

What is acid hydrolysis of an ester?

A

Ester + H2O –> Carboxylic acid + alcohol

22
Q

What happens when a base is used to catalyse the hydrolysis of an ester instead of an acid?

A

the salt of the acid is formed so equlibrium is not reached and more product is formed.

23
Q

Name 4 common uses of esters?

A
  • Solvents,
  • Plasticisers,
  • Perfumes,
  • Food flavourings.
24
Q

What is produced when a triglyceride is reacted with NaOH?

A

Glycerol and a mixture of sodium salts of the acids that form part of the ester.

25
Q

How is biodiesel produced?

A

Triglyceride + KOH

26
Q

What is acylation?

A

The substitution of the acyl group R-CO-R into another molecule.

27
Q

Name 4 acid derivatives that contain an acyl group.

A

Ester, acyl chloride, acid anhydride and amine.

28
Q

What is ab addition-elimination reaction?

A

Nucleophile attacks the C^d+ atom, followed by the loss of Z- (the leaving group. R-CO-Z

29
Q

What is the speed of an addition-elimination reaction governed by? 3 things.

A
  • the size of the charge on the carbonyl carbon which depends on the electron attracting power of Z,
  • How easily Z is lost.
  • How good the nucleophile is.
30
Q

Name 4 typical nucleophiles.

A

Primary amine
Ammonia
Alcohol
Water

31
Q

Why would you use propanoyl chloride instead of propanoic acid when preparing methyl-propanoate from methanol?

A

Its faster as Cl- dissociates more readily.

32
Q

Why would you use propanoic acid rather than propanoyl chloride when preparing methyl-propanoate from methanol?

A

Propanoyl chloride would produce HCl which is toxic, corrosive and harmful to the environment.