Aldehydes And Ketones

Question 1

What group do aldehydes and ketones contain?

Answer 1

Carbonyl group

Question 2

Aldehydes and ketones

Answer 2

•Both contain a carbonyl group •Carbonyl group in aldehyde has a hydrogen atom attached- the aldehyde functional group occurs at the end of the carbon chain •In ketones- carbonyl group is located between two of the carbon atoms within the chain

Question 3

Carbonyl functional group

Answer 3

.

Question 4

Acetylaldehyde(ethanol)

Answer 4

.

Question 5

Propionaldehyde(propanal)

Answer 5

.

Question 6

Acetone( 2-propanone)

Answer 6

.

Question 7

Cinnamaldehyde

Answer 7

.

Question 8

Vanillin

Answer 8

.

Question 9

Formaldehyde

Answer 9

.

Question 10

benzaldehyde

Answer 10

.

Question 11

Nucleophillic Reaction of propanal

Answer 11

.

Question 12

Nucleophillic reaction of acetone

Answer 12

.

Question 13

Idoform Test for methyl Ketone

Answer 13

.

Question 14

fellings solution reaction

Answer 14

Question 15

Tollens reagent in silver mirror test

Answer 15

Question 16

Names of aldehydes end in

Answer 16

Al

Question 17

Names of ketones end in

Answer 17

One

Question 18

Bonding in the carbonyl group

Answer 18

•Oxygen In carbon to oxygen bond far more electronegative •One of the two pairs of electrons that make up carbon to oxygen double bond even more easily pulled towards the oxygen- double bond very polar

Question 19

One Physical property of aldehydes and ketones

Answer 19

Sharp odor

Question 20

Most important reaction of ketones and aldehydes

Answer 20

Nucleophillic addition reaction

Question 21

Nucleophillic addition reaction

Answer 21

The addition of a nucleophile to an electrophillic acceptor

Nucleophile forms new bond to carbonyl group carbon, carbon oxygen double bond breaks, proton bonds to oxygen

Carbonyl group undergoes addition reactions

Question 22

Nucleophillic addition reaction of propanal

Answer 22

.

Question 23

Nucleophillic addition reaction of acetone

Answer 23

.

Question 24

Electrophile

Answer 24

Electrophile is the carbonyl group carbon of the ketone or aldehyde

Question 25

Nucleophile

Answer 25

Nucleophille- negatively charged ion(cyanide ion CN) or slightly negatively charged part of a molecule(lone pair on a nitrogen atom in ammonia NH3)

Question 26

Aldehydes and ketones difference

Answer 26

Aldehyde has hydrogen atom attached to carbonyl group Makes aldehydes very easy to oxidise Ketones don’t have the hydrogen and resistant to oxidation except from powerful agents that can break carbon to carbon bonds

Question 27

Aldehyde and ketone Boiling points

Answer 27

Rise rise as molecules get bigger Size of boiling point governed by strengths of intermolecular forces

Question 28

Solubility in water

Answer 28

Small aldehydes and ketones soluble Solubility falls with increase in chain length

Question 29

Oxidation of alcohols to make aldehydes and ketones

Answer 29

Oxidation of primary alcohol=aldehyde Oxidation of secondary alcohol=ketones

Question 30

Adding of Hydrogen cyanide to carbon-oxygen double bond in aldehydes and ketones produces

Answer 30

Compounds called hydroxynitriles

Question 31

Iodoform test for methyl ketone- description

Answer 31

Reaction with iodine in a NaOH solution and ketones containing a methyl group attached to the carbonyl Produces solid yellow iodoform-strong medical odor and used as an antiseptic

Question 32

Aldehydes and ketones are oxidised using

Answer 32

Benedicts or fehlings solution Silver mirror test

Question 33

Oxidation reaction of aldehydes and ketones

Answer 33

Used to distinguish aldehydes from ketones as ketones can’t be oxidised Blue green cu2+ is reduced for cuprous ion CU+ forming a reddish orange precipitate of Cu2O

Question 34

Silver mirror test- description

Answer 34

Aldehyde treated with tollens reagent- converts aldehydes to carboxylic acids without attacking carbon-carbon bonds Precipitate of silver produced Reveals presence of aldehydes

Question 35

Important aldehydes and ketones/ medical significance- example 1

Answer 35

•Formaldehyde- -colourless irritant gas with disinfectant properties(precipitates proteins) -40% aqueous solution used for conservation of anatomical samples

Question 36

Important aldehydes and ketones/ medical significance- example 2

Answer 36

•Acetylaldehyde- -pungent volatile and flammable liquid -Used as camping fuel in small stoves

Question 37

Reduction of an aldehyde leads to

Answer 37

Primary alcohol

Question 38

Reduction of a ketone leads to

Answer 38

Secondary alcohol

Question 39

Ketoacidosis

Answer 39

-metabolic state caused by uncontrolled production of ketone bodies that cause a metabolic acidosis - results in changes in blood pH -most common cause is diabetic ketoacidosis