C1.6 Plant Oils

Question 1

Why do vegetable oils make good fuels?

Answer 1

Contain a lot of energy

Question 2

Describe the steps of making oil from seeds

Answer 2

-Crushed/pressed -Distilled/decanted/filtered/use a centrifuge

Question 3

Describe how oil can be obtained by steam distillation

Answer 3

-Water and oil are heated till they evaporate -Oil condenses at different temperature to water.

Question 4

Describe the chemical test for unsaturated oils

Answer 4

Add bromine water Turns from orange to colourless if oil is unsaturated

Question 5

Why are oils more suitable for cooking than water

Answer 5

Higher boiling point Cooks food faster (Tastes nicer)

Question 6

What are the conditions needed to hydrogenate an unsaturated oil

Answer 6

60oC Nickel Catalyst

Question 7

How does hydrogenating vegetable oils change their properties?

Answer 7

Raises the boiling point Making it solid

Question 8

Describe how an emulsifier works

Answer 8

• Hydrophilic head is attracted to water
• Hydrophobic tail is attracted to oil
• Oil droplets repel
• Creating suspension of oil throughout the water

Question 9

Describe the risks of eating too much animal fats

Answer 9

High cholesterol

Causes heart disease