Solution: True.

Carbon’s massive molecular structure is made up of covalently bound carbon lattices. Because these connections are extremely strong, they are rigid and have high melting points.

A diamond is a carbon allotrope in which the carbon atoms are organised in a cubic lattice, also known as a diamond lattice. Each carbon atom in a diamond has four neighbours with whom it shares covalent bonds.

The carbon atoms in graphite are organised hexagonally in a planar condensed ring structure. The layers are arranged in a straight line. The atoms within the rings are covalently bound, whereas van der Waals forces hold the layers together loosely.