Question

Why are diamonds extremely hard in nature and have very high melting points?

Answer 1

In the structure of a diamond, each carbon atom is covalently bonded to four other neighbouring carbon atoms. This results in the formation of a rigid tetrahedral structure in three dimensions where one carbon atom is at the centre and the other four carbon atoms are at the corner of the tetrahedron. All these covalent bonds in the diamond are very strong in nature. For all these reasons, diamonds are extremely hard in nature and have very high melting points.