oxidation of food

Question 1

what is oxidation

Answer 1

decrease of oxygen to hydrogen ratio

Question 2

what is reduction

Answer 2

increase of oxygen to hydrogen ratio

Question 3

what does hot copper oxide do

Answer 3

form brown solid

Question 4

what does acidified dichromate solution do

Answer 4

turn from orange to green

Question 5

what does benedicts reagent turn

Answer 5

blue to brick red

Question 6

what does tollens reagent do

Answer 6

form silver mirror

Question 7

oxidation of a primary alcohol

Answer 7

aldehyde which can be oxidised again to a carboxylic acid

Question 8

oxidation of a secondary alcohol

Answer 8

ketone

Question 9

oxidation of a tertiary alcohol

Answer 9

no reaction

Question 10

what is an aldehyde

Answer 10

homologous series containing carbonyl group (C=O) at the end

Aldehydes At the end

Question 11

what is a ketone

Answer 11

homologous series containing carbonyl group (C=O) but cannot be at the end

Question 12

when do you state the number of the carbon the CO group is on in ketones

Answer 12

after butanone

Question 13

can ketones be oxidised

Answer 13

no

Question 14

why can’t tertiary alcohols be oxidised

Answer 14

due to stearic hinderance

Question 15

how can you distinguish between an aldehyde and a ketone

Answer 15

use an oxidising agent as ketones cannot be oxidised so will have no reaction

Question 16

what can aldehydes be used for

Answer 16

for flavour and fragrances

Question 17

example of aldehydes as flavours

Answer 17

vanilla, cinnamon, almonds

Question 18

name for when food goes off

Answer 18

rancid

Question 19

what causes food to go rancid

Answer 19

the edible oils are oxidised

Question 20

how do you prevent foods from going rancid

Answer 20

coat in antioxidants as they are oxidised instead of the thing youre trying to protect

eg vitamin c