Question

2.Three groups of materials are given below Group 1: wood – rock – rubber Group 2: iron – copper – gold Group 3: glass – clear water – air Identify and explain properties which are common for all members of each group. (3m)

Answer 1

Dear student

In group1 all members are good insulators of electricity. The insulators of electricity are the substances which resists the flow of electrons and hence the flow of electricity through them.
In group2 all the members are metals.so they have many properties in common like they all are lustrous, malleable, ductile, good conductors of heat and electricity and have high melting and boiling points. Lustrous means they have shiny surface as they can reflect light. Malleable means they can be made into thin sheets. Ductility means they can be drawn into wires.conductors of heat and electricity means they allow the flow of heat and electricity through them.
In group 3 all the members are transparent in nature. Transparency is the property of substance which allows almost all of the light to pass through it which is encountering it.

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