Integrated Science: Mixtures Part 1

MIXTURES PART 1
INTEGRATED SCIENCE

By Elias Chinyanta

A Substance made up of two or more substances that are not chemically combined.

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​DEFINITION

Mixtures of substances that do not mix uniformly.

- Parts of the mixture do not have the same properties.

Examples

1 Soil 2 Salt 3 Fruit salad

4 sand in water 5 Marbles 6 Corks

7 Oil and water 8 Soups and stews

Heterogeneous mixtures:

Mixtures of substances that mix uniformly.

- All parts of the mixture have the same properties
Examples:

1. sugar water (sugar solution) 2. Sea water

3 Air 4. Blood

​Homogeneous mixtures:

TYPES OF MIXTURES

Multiple Choice

GIVE TWO EXAMPLES OF HOMOGENEOUS MIXTURES

• Sand and gravel
• Saltwater, air
• Oil and water
• Sugar and vinegar

Multiple Choice

GIVE TWO EXAMPLES OF HETEROGENEOUS MIXTURES

• Fruit Salad
• Sugar and Water
• Oil and Vinegar
• Salad, Sand and Salt Mixture

SEPARATING MIXTURES

METHODS:

1. Filtration 2. Simple distillation
3. Fractional distillation 4. Magnetisation
5. Evaporation 6. Crystallisation

It is a method of separating insoluble solids from a liquid using a filter paper.
- Insoluble substances: Substances that do not dissolve.
- The mixture of sand and water or the mixture of chalk particles and water can be separated using the process of filtration.
- The filter paper is inserted into the funnel.
- The mixture is poured. - Water molecules will pass through the filter paper as filtrate
- Sand or chalk particles will remain on the filter paper.

FILTRATION

Fill in the Blank

State six separating techniques for mixtures.

Multiple Choice

When is the filtration method used to separate mixtures?

• When separating gas-liquid mixtures.
• When separating solid-solid mixtures.
• When separating liquid-liquid mixtures.
• When separating solid-liquid mixtures.

- This is the process of vapourising the liquid and condensing the vapour. - It can be used to separate the liquid water from the salt solution. - The liquid has usually a very much lower boiling point than that of a dissolved solid. - The liebig condenser is used to cool the vapour and this vapour is collected as distillate. - The diagram below shows the simple distillation.

SIMPLE DISTILLATION

Fill in the Blank

When is it suitable to use the simple distillation method?

Multiple Choice

When is it suitable to use the simple distillation method?

• When the components have significantly different boiling points.
• When the mixture is a solid and needs to be separated.
• When the components are soluble in each other.
• When the components have identical boiling points.