2.6 Oxidation of Food

Question 1

What functional group is in Ketones? and how do they end?

Answer 1

Carbonyl group (C=O)
ending -one

Question 2

What functional group is in Aldehydes? and how do they end?

Answer 2

Functional Group -CHO
ending -al

Question 3

What is the general formula for Aldehydes?

Answer 3

CnH2nO

Question 4

What is the general formula for Ketones?

Answer 4

CnH2nO

Question 5

What is another name for the Aldehydes?

Answer 5

Alkanals

Question 6

What is another name for the Ketones?

Answer 6

Alkenones

Question 7

How many stages can Primary Alcohols be oxidised in?

Answer 7

2 - Alcohol to aldehyde
- Aldehyde to carboxylic acid

Question 8

How many stages can Secondary Alcohols be oxidised in?

Answer 8

1 - To produce ketones

Question 9

How many stages can Tertiary Alcohols be oxidised in?

Answer 9

None

Question 10

Describe Oxidation

Answer 10

Loss of e- / H
Gain of O

Question 11

Describe Reduction

Answer 11

Gain of e- / H
Loss of O

Question 12

What colour change happens to Copper (II) oxide?

Answer 12

Black to solid brown

Question 13

What colour change happens to Acidified Potassium Dichromate?

Answer 13

Orange to green

Question 14

What colour change happens to Fehling’s (Benedict’s) Solution?

Answer 14

Blue to brick red

Question 15

What colour change happens to Tollens reagent?

Answer 15

Colourless to silver mirror

Question 16

What is the term when food has become oxidised?

Answer 16

Rancid

Question 17

What are antioxidants?

Answer 17

Molecules that reduce the rate of oxidation reactions

Question 18

What is a free radical?

Answer 18

A highly reactive species with an unpaired electron

Question 19

How to antioxidants work?

Answer 19

They give an electron to the free radical