Oils and emulsions

Question 1

What are the two ways of extracting oil from seeds

Answer 1

• pressing

* distillation

Question 2

What happens when you mix oil and water

Answer 2

They do not mix they seperate

Question 3

Why is it bad too add too much oil to our diets

Answer 3

• lots of calories

* could be turned into gat if not burned off

Question 4

Why are oils part of our diet

Answer 4

• add nutrients

* add energy to out food

Question 5

What is the smoking temperature of oil

Answer 5

Temperature which oil catches fire

Question 6

Why do things cool quicker in oil than water

Answer 6

Water boils at 100 degrees and oil gets to a much higher temperature

Question 7

Why is vegetable oil used to cook food instead of water

Answer 7

• improve taste
• cools quicker
• adds nutrients

Question 8

What is the bromine test

Answer 8

Add bromine water to unsaturated oil and it will decolourise

Question 9

What is a hydrophollic

Answer 9

A molecule attracted to water

Question 10

Whats a hydrophobic

Answer 10

A molecule that’s attracted to oil

Question 11

What is an emulsion made off

Answer 11

Emulsions are made up of lots of droplets of one liquid suspended in another liquid

Question 12

What happens with an emulsions when you add more oil

Answer 12

The more oil the thicker it is

Question 13

What are emulsifiers

Answer 13

Molecules with one part attracted to water and another attracted to oil

Question 14

How are emulsifiers used in food

Answer 14

• emulsifiers stop emulsions from separating out and give them a longer shelf life
• allow food companies to produce food thats lower in fat but still has good texture

Question 15

What is the bromine test

Answer 15

Add bromine water to unsaturated oil and it will decolourise

Question 16

What is a hydrophollic

Answer 16

A molecule attracted to water

Question 17

Whats a hydrophobic

Answer 17

A molecule that’s attracted to oil

Question 18

What is an emulsion made off

Answer 18

Emulsions are made up of lots of droplets of one liquid suspended in another liquid

Question 19

What happens with an emulsions when you add more oil

Answer 19

The more oil the thicker it is

Question 20

What are emulsifiers

Answer 20

Molecules with one part attracted to water and another attracted to oil

Question 21

How are emulsifiers used in food

Answer 21

• emulsifiers stop emulsions from separating out and give them a longer shelf life
• allow food companies to produce food thats lower in fat but still has good texture

Question 22

What is the bromine test

Answer 22

Add bromine water to unsaturated oil and it will decolourise

Question 23

What is a hydrophollic

Answer 23

A molecule attracted to water

Question 24

Whats a hydrophobic

Answer 24

A molecule that’s attracted to oil

Question 25

What is an emulsion made off

Answer 25

Emulsions are made up of lots of droplets of one liquid suspended in another liquid

Question 26

What happens with an emulsions when you add more oil

Answer 26

The more oil the thicker it is

Question 27

What are emulsifiers

Answer 27

Molecules with one part attracted to water and another attracted to oil

Question 28

How are emulsifiers used in food

Answer 28

* emulsifiers stop emulsions from separating out and give them a longer shelf life * allow food companies to produce food thats lower in fat but still has good texture

Question 29

What is an emulsion

Answer 29

A mixture of things that normally don't mix | Water and oil

Question 30

What do you need to make an emulsion

Answer 30

An emulsifier

Question 31

List 4 uses of emulsions

Answer 31

* paint * moisturiser * mayonnaise * milk

Question 32

What can vegetable oils such as rapeseed and soybean oil be turned into and why

Answer 32

Fuels because they provide a lot of energy and really suitable for use as fuels

Question 33

What is 'polymerisation'

Answer 33

A reaction of monomers together in a chemical reaction

Question 34

List 3 problems with plastics:

Answer 34

* expensive to separate from rubbish * can't reshape them a lot * takes a lot of energy to melt them down

Question 35

How do you make ethanol by fermentation of sugars

Answer 35

* sugar cane plants are crushed and soaked in water for one day * the solution is separated by filtration * yeast is added to the sugar solution and fermented for three days * the yeast is separated from the solution of water and ethanol by filtration * ethanol is separated by fractional distillation

Question 35

How do you make ethanol by hydration of ethene

Answer 35

* ethene comes from crude oil * fraction distillation longer hydrocarbons are cracked * smaller alkanes such as ethene are produced * the reaction of ethene with steam to produce ethanol is known as hydration * it takes place in a reactor at high temperatures and pressures, with a catalyst of phosphoric acid

Question 36

Describe the method of pressing

Answer 36

* seed oils are collected and crushed * mixed with water and left to stand for a day * pressed to extract oil * oil separated from water and bottled

Question 37

Describe the method of distillation

Answer 37

* crushed plants and solvent are heated in a flask * the mixture evaporates * the gas then condenses * the water made is left in a flask as they separate the water and oil

Question 38

Discuss the positive and negatives with fermentation of sugars

Answer 38

* Renewable * has a natural catalyst (yeast in enzymes) * batch process * slow process * impure - needs to be separated from water and ethanol

Question 39

Discuss the positives and negatives with the process of hydration of ethene

Answer 39

* continuous process * fast process * 100% pure * non renewable * has a catalyst of phosphoric acid (dangerous)

Question 40

What is the process of pressing

Answer 40

1) seeds/oils are collected and crushed 2) mixed with water and left to stand 3) pressed to extract oil 4) oil is separated from water and bottled

Question 41

What is the process of distillation

Answer 41

1) crushed plants and solvent are heated in a flask 2) the mixture evaporates 3) the gas then condenses 4) the water made is left in the flask

Question 42

What are the positives for fermentation of sugar

Answer 42

Renewable | Yeast catalyst which breaks it down in enzymes

Question 43

What are the negatives for fermentation if sugars

Answer 43

Batch process Slow Impure - separated from water and ethanol

Question 44

What are the positives of hydration of ethene

Answer 44

Continuous process Fast 100% pure

Question 45

What are the negatives for hydration of ethene

Answer 45

Non renewable | Phosphoric acid catalyst