15B.2

Question 1

what is more easily oxidized ketones of aldehydes?

Answer 1

aldehydes

Question 2

what are aldehydes oxidized to

Answer 2

carboxylic acid

Question 3

what are aldehydes reduced to

Answer 3

primary alcohols

Question 4

what are ketones reduced to

Answer 4

secondary alcohol

Question 5

what are ketones oxidized to

Answer 5

they are not easily oxidized

Question 6

what is the regent that ketones and aldehydes are reduced in

Answer 6

lithium aluminum hydride LiAlH4

Question 7

in reduction reactions how is the reducing agent written

Answer 7

[H]

Question 8

what are reduction reactions for

Answer 8

to show the conversion of ketones and aldehydes to alcohols

Question 9

how does a reduction reaction look like

Answer 9

page 117

Question 10

what are oxidation reaction included for

Answer 10

to distinguish between aldehydes and kertones

Question 11

what are the four reagents that can oxidise aldehydes to carboxylic acids and there colour changes

Answer 11

page 117

Question 12

how can we carry out the oxidation reactions

Answer 12

by mixing carbonyl groups with oxidizing agents and then leaving the mixture in a beaker of hot water

Question 13

what are the safety protection that we need to take when carrying out oxidation reactions

Answer 13

wear eye protection, avoid skin contact, and only heat the water with an electric kettle and not with a flame

Question 14

how does a oxidation reaction look like

Answer 14

page 118

Question 15

how can we test if a mixture contains a ketone or a aldehyde

Answer 15

by adding Fehling’s solution, or benedict solution, or tollens’ reagent and seeing if there is a colour change, if there is one then its a aldehyde

Question 16

what is the triiodomethane or iodoform reaction

Answer 16

a reaction where a carbonyl compound with the group of CH3O is added to an alkaline solution of iodine and the mixture is then warmed and cooled and a pale yellow precipitate (CHI3) forms

Question 17

what carbonyl compounds have a positive result for the triiodomethane reaction

Answer 17

ones with group of CH3O like only on aldehyde - ethanal, and all the methyl ketones (those with a carbonyl group as the second carbon in the chain)

Question 18

why do some alcohols have a positive result for the iodoform or triiodomethane test

Answer 18

because it is carried in oxidizing conditions so an secondary alcohol with terminal methyl group can be oxidized to form a ketone then react to form a pale precipitate (CHI3)