Chapter 4: The variety of resources on earth

o 2.1. Living things need resources on earth to sustain life.o e.g air, ……………, ………………,………………..,……………………

2.2.

2.3. What is elements? – made up of only ………. type of …………./particle. - the simplest substance.

- divided into …………… and ……………………

The differences between metal and non-metal

Terms of Metal Non-metalAppearances

………………. surfaces

…………… surfaces

Differences

Differences in terms ofAppearances Hardness Conductivity of heatConductivity of electricity

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Resources on earth

Types

E……………. C……………..

Metals Non-metals

Examples Examples

M…………..

Examples

Conductivity of heat …………..

conductor of heat

………….. conductor of heat

Conductivity of electricity ……………

conductor of electricity

…………… conductor of electricity

Hardness ………………. ……………….

Melting point……………….. ………………..

2.4. What is compound?o Substances that made up of ………. or more types of atoms which combined

c…………….o Can be separated c………………...o e.g. carbon dioxide, water, sodium chloride, ammonia, methane.

2.5. What is mixtures?o Substances that made up of two or more substances/atoms which combined

p……………….o Can be separated p……………………..o e.g. air, soil, sea water, junk food, blood.

2.6. The method to separate the components of a mixture.

Filtration To separate the mixture of sand and sea water/waterUsing a magnet To separate mixture of iron filings and sulphurEvaporation To separate the mixture of salt and water 2.7. Differences of properties between elements, compounds & mixtures.

Properties Elements Compound MixturesMade up of Only ……….. type

of atom…………. or more of atoms

Two or more types of substances/atoms

How is it formed Naturally Combined C……………….

Combined P………………..

Able to separate Cannot Chemical method such as electrolysis.

Physical method such as evaporation, filtration.

Changes during preparation

No Heat released or heat absorbed

No change

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2.8. Explain the importance of variety of earth’s resources to man.Air contain ……………… for respiration.Green plants use …………………. & water for photosynthesis.Soil supplies plants with ………………. & water.Natural gas is used for ……………………

2.8.1. State the meaning of preservation & conservation of resources on earth.

Preservation : setting up forest reserves, national ……….. & marine parks.Conservation : using earth’s resources wisely & not in wasteful manner.

The importance of preservation & conservation of resources on earth.a) recycling of paper will reduce the cutting down of trees.b) conserving clean water prevents water shortage.

Practice 3R – reduce, reuse & recycle.

EXERCISE

1. Give 3 examples of fossil fuels.(a) ………………………………..(b) ……………………………….(c) ……………………………….

2. Why do living things need air?……………………………………………………………………………

3. Give 3 differences between metals & non-metals.i) ……………………………………………………………………………….ii) …………………………………………………………………………….iii) ………………………………………………………………………………

4. The following is the examples of substances.

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Carbon dioxide sodium Calcium carbonate waterGlucose iodineSulphuric acid bronzeMercury orange juiceIce-cream silver

Classify these substances into elements, compounds & mixtures.Elements Compounds Mixtures

5. Suggest ways to reduce the amount of rubbish we produce.………………………………………………………………………………………………………………………………………………………………………………

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