D.Answer the following questions:-
Question
1.What are Rock?
Ans.1 Any
natural mass of mineral matter that makes up the earth’s crust is called a
rock.Rocks can be different colour, size and texture
Ans.2 Metamorphic rocks are formed by the process of metamorphism. The term
metamorphism means transformation. It may involve both physical as well as
chemical changes in the pre-existing rocks.
Que-3 What
are sediments? Write names of three types of
sedimentary rocks?
Ans-3 When the igneous rocks are exposed on the earth’s surface, they are
broken down by the agents of weathering such as wind, ice and water into small
fragments. The small fragments are called sediments.
The three different
sediment rocks are Shale, Sandstone and Conglomerate.
Que-4 Describe the interior structure of the earth?
Ans-4 The structure of the earth can be compared to an onion. The earth is made
up of several concentric layer with one inside the other. The uppermost layer
over the earth surface is called curst, the second layer is known as mantle. And the innermost layer is
called core.
Ans-5 The chemical substances which from rocks are called minerals. Quartz is
one of the most common mineral found on the surface of earth.
Some of the minerals are Gold,
Sulphur, Diamond and graphite.