8th Social Science - Geography - Lesson 01 - ROCKS AND SOILS

UNIT 1 – ROCKS AND SOILS

I. Choose the Correct Answer

1. Which of the following is known as sphere of rocks?

a) Atmosphere
b) Biosphere
c) Lithosphere
d) Hydrosphere

Answer: (c) Lithosphere

2. World Soil Day is observed on

a) 15th August
b) 12th January
c) 15th October
d) 5th December

Answer: (d) 5th December

3. Fossils are found in

a) Sedimentary rocks
b) Igneous rocks
c) Metamorphic rocks
d) Plutonic rocks

Answer: (a) Sedimentary rocks

4. The top layer of soil is called

a) Organic layer or humus
b) Topsoil
c) Subsoil
d) Bedrock

Answer: (b) Topsoil

5. Ideal soil for growing cotton is

a) Red soil
b) Black soil
c) Alluvial soil
d) Mountain soil

Answer: (b) Black soil

II. Fill in the Blanks

• Scientific study of rocks is called Petrology.
• Red Soil is suitable for millet cultivation.
• The "skin of earth" is Soil.
• Taj Mahal was built using White Marble.
• Igneous Rocks are called primary rocks.

III. True or False

• Igneous rocks are called primary rocks – True
• Slate is formed from shale – True
• Red soil is formed by leaching – False
• M-Sand is used as an alternative to natural sand – True
• Volcanic mountains are covered with sedimentary rocks – False

VII. Give Reasons

1. Why are chemical sedimentary rocks found in reservoir beds?

• They are formed from minerals dissolved in water.
• Minerals settle after evaporation.
• Hence they occur in reservoir beds.

2. Why are igneous rocks found in volcanic regions?

• Igneous rocks are formed from magma.
• Magma cools and solidifies.
• Therefore they occur near volcanoes.

Class 8 Science | Unit 1 – Rocks and Soils