natures chemistry

Question 1

How are proteins formed?

Answer 1

Through a condensation reaction

Question 2

What is a condensation reaction?

Answer 2

When amino acids join together and water is removed. A peptide link is formed.

Question 3

What are essential amino acids?

Answer 3

They are amino acids that the body needs but cannot be made, therefore it’s taken in through the diet

Question 4

How do you break down proteins

Answer 4

Through a hydrolysis reaction

Question 5

Proteins are….

Answer 5

Major structural material found in animal tissues

Question 6

2 types of proteins

Answer 6

Fibrous- long, spiral chains folded into long thin shapes. Strong and insoluble in water

Globular- involved in regulation. Spiral chains and folded into spherical shapes and soluble in water

Question 7

During cooking …

Answer 7

Proteins are denatured

Question 8

What groups do amino acids have?

Answer 8

A carboxyl group (COOH)
An amino acid group (NH2)

Question 9

what’s another name from glycerol?

Answer 9

propane-1,2,3-troil

Question 10

fatty acids are …

Answer 10

saturated. so they are closely packed together therefore the melting and boiling points are higher cause the bonds are closer and stronger LDF’s

Question 11

oils are …

Answer 11

unsaturated. so they have kinked bonds so they aren’t closely packed together therefore they have weaker LDF’s

Question 12

oxygen to hydrogen ratio

Answer 12

oxidation is increase
reduction is decrease

Question 13

primary alcohol oxidation

Answer 13

primary alcohols to aldehyde - done by acidified dichromate solution
aldehyde to carboxylic acid - done by tollens reagent

Question 14

secondary alcohol oxidation

Answer 14

secondary alcohol to ketone - done by acidified dichromate solutions

Question 15

tertiary alcohol oxidation

Answer 15

no oxidation

Question 16

primary alcohol placement

Answer 16

carbonyl functional group joined to carbon

Question 17

secondary alcohol placement

Answer 17

carbonyl functional group joined onto 2 other carbons

Question 18

tertiary alcohol placement

Answer 18

carbonyl functional group joined onto 3 other carbons

Question 19

many flavour and aroma molecules are …

Answer 19

aldehydes

Question 20

oxidation of foods gives it a …

Answer 20

rancid flavour

Question 21

antioxidants prevent…

Answer 21

unwanted oxidation from occurring

Question 22

antioxidants are;

Answer 22

easily oxidised
they themselves are oxidised instead of the compounds they are protecting
easily identified as the substance being oxidised in a redox reaction

Question 23

What’s the test to find unsaturated compounds

Answer 23

Bromine test

Question 24

Formation of an ester

Answer 24

Alcohol + carboxylic acid -> ester + water

Methanol + ethanoic acid -> methyl ethanoate + water

Question 25

Saturated-

Answer 25

Single bonds

Question 26

Unsaturated-

Answer 26

Double bonds

Question 27

What happens to saturated bonds with bromine water

Answer 27

Saturated do NOT decolourise bromine, stays orange

Question 28

What happens to unsaturated bonds with bromine water

Answer 28

Unsaturated bonds decolourise bromine solution quickly

Question 29

Isomers are compounds…

Answer 29

With the same molecular formula but different structural formulae

Question 30

Physical properties of compounds can be predicated by considering…(4)

Answer 30

-presence of OH or NH bonds - spatial arrangement of polar covalent bonds -polarities of solute and solvent -molecular size of molecules

Question 31

What is the OH group

Answer 31

Hydroxyl

Question 32

What is the COOH group

Answer 32

Carboxyl

Question 33

What do carboxylic acids name finish with

Answer 33

-oic acid

Question 34

What’s the name to describe water that has high levels of dissolved metal ions

Answer 34

Hard water

Question 35

What do aldehydes finish with and what is there structure

Answer 35

-al COH

Question 36

What do ketones finish with and what is there structure

Answer 36

CO -one

Question 37

What functional group do aldehydes and ketones have

Answer 37

Carbonyl functional group O = -C-

Question 38

Antioxidants are…

Answer 38

-substances that are easily oxidised - they are oxidised instead of the compounds they protect - can be identified as the substance being oxidised in a redox reaction

Question 39

What does exposure to UV light cause

Answer 39

It provides sufficient energy for bonds to be broken Causes sunburn and accelerates skin aging Sun-block prevents Uv from reaching the skin

Question 40

What are free radicals

Answer 40

They are atoms or molecules with an unpaired electron UV light breaks the bonds to form free radicals They are highly reactive due to the unpaired electron

Question 41

Definition of an emulsifier

Answer 41

It prevents polar and non-polar substances from separating into layers