Question

Why is Diamond different from non-metals?

Answer 1

Diamond is a type of solid crystals which is made up of constituent particles which are joined with each other by the formation of covalent bonds. The Constituent particles of diamond are carbon atoms which are non-metal atoms and it forms covalent solid.

Complete answer:
Diamond is made up of a large number of carbon atoms in which each carbon atom is bonded with four other adjacent carbon atoms to form a large continuous network or crystal. Diamond has a definite shape and hence it is an example of a crystalline solid.
There is some basic difference between metal and non-metals-

PROPERTY	METAL	NON-METAL
Electron donor/acceptor	Electropositive in nature	Electronegative in nature
Physical appearance	Shiny or lustrous	Dull in colour
Physical state	Solid in nature	Solid, liquid, or gas
Conductivity	Good conductor of electricity	Bad conductor of electricity
Malleability	Convert into thin sheet	Do not convert into thin sheet
Ductility	They can be drawn into wires	They cannot be drawn into wires
Tensile strength	Highly tensile	Low tensile
Density	High density	Low density
Melting point	Sharp melting point	Low melting point
Boiling point	High boiling point	Low boiling point
Examples	platinum, gold, silver	diamond, graphite, sulphur

Diamond has specific property which differentiate it from non-metals such as-

PROPERTY	DIAMOND	NON-METAL
Conductivity	It is an insulator and does not conduct electricity in solid as well as in liquid phase.	Nonmetals are bad conductors but some may conduct electricity like graphite.
Physical stability	Highly stable in nature	They are less stable physically than diamonds.
Hybridization	$s{p^3}$	$s{p^2}$ or $s{p^3}$
Melting temperature	Diamond has exceptionally high melting temperature i.e., ${4027^ \circ }C$	Melting point of nonmetal is not so high like melting point of sulphur is ${115.2^ \circ }C$
Malleability	Diamond is not malleable in nature	Non-metals are malleable in nature.

Note:
Covalent crystals are also known as giant molecules because of their ability to form a large network of atoms. They are hard and poor conductors of electricity due to formation of covalent bonds. Other examples of covalent compounds include quartz $\left( {Si{O_2}} \right)$ , boron nitride $\left( {BN} \right)$ , carborundum.