Minerals
❐ Geology is the study of rocks and minerals that form the Earth.
❐ Scientists who study the Earth to find out how and where minerals and rocks occur are called geologists. A geologist is consulted while building houses or digging a tube well, or building a bridge or a tower.
❐ Minerals are inorganic chemical compounds or elements that occur naturally. They are the building blocks of the Earth and are the main substances that make up rocks.
Query Corner
1. Name the following.
a. It is the study of rocks and minerals.
= Geology;
b. This mineral is used to produce nuclear energy.
= Uranium;
c. It is the main ore of aluminium.
= Bauxite;
d. This mineral is composed of calcium carbonate.
= Limestone;
e. It is found in association with petroleum in the sedimentary beds.
= Natural Gas;
2. Match the following.
=
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a. Anthracite |
i. Iron ore. [c] |
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b. Non-ferrous mineral |
ii. Petroleum. [d] |
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c. Magnetite |
iii. Mica. [e] |
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d. Fossil fuel |
iv. Bauxite. [b] |
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e. Non-metallic mineral |
v. coal. [a] |
3. State whether the following statements are 'true' of 'false'.
a. Scientists who study the Earth to find out how and where minerals and rocks occur are called physicists. [F]
b. Metallic minerals are poor conductors of heat and electricity. [F]
c. Gold is a soft metal with high lustre. [T]
d. Peat is the best form of coal. [F]
e. Minerals are exhaustible or non-renewable natural resources. [T]
4. Answer the following questions.
a. What are rocks?
= Rocks are those solid materials that make up the outer layer or crust of the Earth.
b. How are rocks different from minerals?
=
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Rocks |
Minerals |
|---|---|
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a. Rocks are those solid materials that make up the outer layer or
crust of the Earth. |
a. Minerals are naturally occurring useful substances with definite
physical properties and chemical compositions. |
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b. Rocks are made up of one or more minerals. |
b. Minerals are not made up of rocks. They are made up of chemicals. |
c. What are ores? Give two examples.
= Ores are those rocks that contain metallic minerals only. Examples :- Manganese ore and iron ore are so called as we derive metals from them.
d. What are metallic and non-metallic minerals?
= Metallic minerals contain metals. They have a shine or lustre of their own. Example :- iron, copper, gold, silver etc.
Non-metallic minerals do not contain minerals in it. Example :- mica, gypsum, chalk, calcium etc.
e. What are mineral fuels? Why are they also known as fossil fuels?
= Coal, petroleum and natural gas are examples of 'mineral fuels' or 'fossil fuels'.
They are known as fossil fuels as they are produced from the dead and decomposed plants and animals deep down the earth.
f. Name the major producers of copper in the world. What are its uses?
= Major producers of copper in the world are - China, Mexico, Chile, Peru, Congo, Zambia.
Uses of copper :- It is good conductor of heat and electricity.
It is used in electric wires, and alloys like bronze and brass.
g. Mention any two uses of coal.
= Two uses of coal are -
❐ Coal is used to generate thermal power.
❐ A large amount of coal is required in the cement, chemical and steel industries.
h. Explain the two important methods of mining.
= Two important methods of mining are -
❐ Opencast mining :- This is a type of surface mining that is carried out when minerals occur close to the surface. The top layer of the rock and soil is stripped, and the mineral deposit is mined by strip-mining or the open pit method.
❐ Shaft mining :- This is a type of underground mining carried out usually for minerals such as coal, which lie at great depths below the ground. A long vertical tunnel or shaft is dug to bring out the minerals to the surface.
i. Mention any three hazards of mining.
= three hazards of mining are -
❐ Mine dust creates air pollution and its inhalation leads to the malfunctioning of lungs in human beings and other living creatures.
❐ When mine dust covers the soil, it inhibits water percolation and thus makes soil infertile.
❐ Mine tailings, the mud-like waste material released from mines, may create water pollution as they are toxic in nature.
j. State any three methods of conservation of minerals.
= Three methods of conservation of minerals are -
❐ The principle of 3 Rs - Recycle, Reuse and Reduce - should be followed. It means reducing wastage of resources by recycling and reusing them.
❐ Use renewable substitutes, wherever possible. For example, using hydroelectricity or solar power to reduce pressure on fossil fuels.
❐ Wastage during the process of mining and processing along with pilferage during transportation should be put to an end.
5. Thought-provoking questions.
a. Differentiate between metallic and non-metallic minerals.
=
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Metallic Minerals |
Non-metallic Minerals |
|---|---|
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They contain metals and thus have a shine or lustre of their own. |
An absence of metals gives non-metallic minerals a dull appearance. |
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They are usually ductile and malleable and do not break easily. |
These minerals are not ductile and malleable; they are brittle. |
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They are good conductors of heat and electricity. |
They are poor conductors of heat and electricity. |
b. Why should we use minerals cautiously and preserve them?
= We should use minerals cautiously and preserve them because -
❐ Minerals are exhaustible or non-renewable natural resources that take millions of years to form.
❐ A rapid increase in population has triggered a tremendous growth in the industrial sector to meet the increased demand for goods. This trend is gradually depleting the planet's mineral resources.