aseel samaro understanding distillation. distillation is used in making perfumes, fuels (such as...

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Aseel Samaro Understanding distillation

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Page 1: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

Aseel Samaro

Understanding distillation

Page 2: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)
Page 3: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)
Page 4: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka).

It is an important separation process involving heating and cooling.

Introduction

Page 5: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

On a cold day water vapour from a bath or kettle can condense on a cold surface.

It cools down and turns back to water.

This is what happens in distillation.

Liquid mixtures can be separated using distillation.

Heating and cooling

Page 6: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

Name three substances that are made using distillation.

Why does steam turn into liquid water when it touches a window?

Page 7: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)
Page 8: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

When water boils it is hard to catch all of the water vapour because it mixes into the air.

In distillation the vapour is cooled, which allows it to be collected as a liquid.

2000 years ago Greek scientists, known as alchemists, invented a way to distil liquids.

It was so successful that the design was on sale until 1860.

Catching steam

Page 9: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

The distillation apparatus that we use today is based on the same principle of heating and cooling.

The major improvement is the Liebig condenser, which is a double glass tube.

The hot vapour from the boiling liquid flows through the inner tube, while cold water runs though the outer tube.

This keeps the inner glass tube cold and condenses most vapours easily. The liquid collected at the end is called the distillate.

Page 10: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)
Page 11: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

Why is the alchemists’ method a better method of separation than just heating a mixture of liquids?It stops the steam/vapour/water escaping; captures the steam/vapour/gas and turns it back/ condenses it to water/liquid.

Why is the Liebig condenser better than the alchemists’ equipment?The condenser has water to keep the tube cold; which makes condensation happen more quickly; because it is

colder.

Explain the safety checks you would use to separate a mixture safely.clamp flask above heat source

glass not cracked/brokennot too much liquid in distillation flask to boil over cold water for condenser is on and does not leak

collection beaker is in the right place/no spills.

Page 12: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

There are two changes of state in distillation.

First, a liquid is evaporated by heating and then the cooled vapour condensed back to a liquid.

When salty water is heated, only the water (solvent) changes state and the salt (solute) is left behind.

The water produced is called distilled water.

Distilling mixture

Page 13: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

Different liquids boil at different temperatures – for example, ethanol boils at 78 °C and water at 100 °C.

This means that mixtures of liquids can be separated using distillation.

A thermometer at the top of a distillation flask shows the temperature of the vapour being condensed and hence identifies the substance being separated.

Distillation is an effective way of purifying alcohol or increasing the concentration of alcoholic drinks.

It is also useful for separating flammable liquids like petrol and diesel because the vapours never come into direct contact with the flame.

Page 14: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)
Page 15: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)
Page 16: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

Why is distillation a better way to separate salt and water than crystallisation?It is quicker

collects the water and the salt less water/salt is lost.

Why is a thermometer important in distillation?The thermometer gives the temperature of the vapour/boiling point

so you know which substance is being separated – i.e. which is a gas (in the condenser) and which is still liquid (in the flask).

Why is distillation a good method for separating petrol and diesel?They are flammable liquids; a direct flame cannot be used.

Explain how water and ethanol are separated.They have different boiling points/ethanol has a lower boiling point/turns to vapour/gas first; and can be condensed and collected before the

water boils.

Page 17: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

Steam distillation is used to obtain essential oils from plants such as herbs and flowers.

The products are used in aromatherapy, flavourings in foods and drinks, and as scents in perfumes, cosmetics and cleaning products.

Did you know ?

Page 18: Aseel Samaro Understanding distillation.  Distillation is used in making perfumes, fuels (such as petrol) and alcoholic drinks (such as vodka)

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