State the property utilized in the following :
(i) Graphite in making electrodes.
(ii) Electric wires are coated with polyvinyl chloride (PVC) or a rubber like material.
(iii) Metal alloys are used for making bells and strings of musical instruments.

Explanation

(i) Graphite is a good conductor of electricity in spite of the reason that it is a non-metal. It is a crystalline allotropic form of carbon and its electrical conductivity is because of the presence of a free electron in each atom which is available to conduct electricity. (Carbon and its Compounds)
(ii) Electric wires are generally made of metals like copper and aluminium which are good conductors of electricity. In order to insulate, these are kept covered with PVC or any other rubber like material.
(iii) Gun metal (alloy of Cu = 90 & Sn = 10 parts) is used for making bells because it is very heavy. Similarly, stainless steel or any other variety of steel is used for the manufacture of strings of musical instruments since it is ductile in nature.