Class 5 Science - Rocks And Minerals - Question Answers

Q1: What are rocks made of, and why are they considered natural resources?
Ans: Rocks are made up of small grains called minerals. They are considered natural resources because they provide us with various metals, non-metals, and fossil fuels.

Q2: Explain the three types of rocks based on their formation.
Ans: Rocks are classified into three types based on their formation:

• Igneous rocks form from the cooling and hardening of hot molten rocks.
• Sedimentary rocks are formed from the accumulation and cementation of rock particles in water bodies.
• Metamorphic rocks result from changes in existing rocks due to high temperature and pressure.

Q3: What are some examples of igneous rocks, and what are their uses?
Ans: Examples of igneous rocks include Granite (used for kitchen counters), Pumice (used in polishing), Obsidian (used for jewelry and cutting tools), and Basalt (used for road construction).

Q4: How are sedimentary rocks formed, and can you name some types of sedimentary rocks?
Ans: Sedimentary rocks are formed when tiny pieces of rocks, sand, and shells get carried by wind or water and then settle down in layers. Over a long time, these layers get pressed together and become hard rocks. This happens mostly in rivers, lakes, and oceans.

Types of sedimentary rocks:

• Sandstone – made from sand.
• Shale – made from mud or clay.
• Limestone – made from shells and sea animals.

Q5: Describe how metamorphic rocks are formed and provide examples.
Ans: Metamorphic rocks are formed when other rocks change because of heat and pressure. This usually happens deep under the ground. The rocks do not melt, but they change their shape, texture, or minerals.

Examples of metamorphic rocks:

• Marble – formed from limestone.
• Slate – formed from shale.

Q6: What are minerals, and how are they related to rocks?
Ans: Minerals are naturally occurring chemical substances found on Earth. They are the building blocks of rocks, as all rocks are composed of minerals.

Q7: Explain the difference between metallic and non-metallic minerals, and provide examples of each.
Ans: Metallic minerals contain metals like gold, iron, aluminum, and copper. Non-metallic minerals do not contain metals. Examples of metallic minerals include gold (used for jewelry) and iron (used for utensils), while non-metallic minerals include graphite and mica.

Q8: How are fossil fuels like coal and petroleum formed, and what are their primary uses?
Ans: Coal is formed from the buried remains of plants in swampy forests over millions of years. It is used as fuel for cooking, electricity generation, and in steam engines. Petroleum is formed from the remains of marine plants and animals buried under the sea over millions of years. It is used as fuel in various forms and for dry cleaning.

Q9: Why is it important to conserve coal and petroleum?
Ans: Coal and petroleum are limited resources, and their excessive use can deplete them. Burning them also causes pollution and can lead to harmful diseases. Therefore, it's crucial to conserve these resources and use non-polluting energy sources like solar energy.

Q10: How can we use the energy of the sun, and why is it a sustainable option?
Ans: Solar energy can be used for cooking, electricity generation, and more. It's sustainable because the sun's energy is abundant and will never run out, plus it doesn't cause pollution. Solar cells convert sunlight directly into electricity, making it a clean and renewable energy source.