Which of the following is correct regarding diamond?
(i) Diamond is covalent, yet it has high melting point.
(ii) It used for cutting glass, making borers for rock drilling, and for making abrasives.
(iii) It is used for making precious gems and jewellery.
(iv) It is used for making fies for drawing this wires from metals.

Options

A. (i), (ii)
B. (i), (ii), (iii)
C. (i), (ii), (iii), (iv)
D. (i), (iii), (iv)

Answer

C

Explanation

Diamond has a rigid three-dimensional netwoek of `C` atoms held together by strong `C-C` bonds which are very difficult to break. This makes diamond a very hard substance with abnormally high melting point. Diamond is a solid to over `4000^(@)C` because an enormous amount of energy is required to break these strong covalent bonds.
Because of its hardnesss, it is used for grinding and polishing of hard materials. When diamond is cut and polished, brilliant light is refracted from its surface. This makes diamond a precious gemstone.