Question

explain the difference: diamond and graphite

Answer 1

refractive index of diamond is 2.4 and refractive index of graphite is 2.1
diamond is made from coal and graphite is used in pencil lead..

Answer 2

Diamond and graphite are both giant covalent substances made entirely of carbon atoms. Both have chemical formula , but they do not have a molecular formula.

Diamond and graphite are allotropes of carbon. Allotropes are different forms of the same element due to differences in structure.

Molecular structure

Diamond: Giant covalent structure, with each carbon covalently bonded to four other carbon atoms in a tetrahedral arrangement to form a rigid structure.

Graphite: Giant covalent structure, with each carbon covalently bonded to three other carbon atoms in a hexagonal arrangement.

Hardness

Diamond: Extremely hard. Due to rigid, tetrahedral arrangement of carbon atoms.

Graphite: Soft. Layers of hexagonally arranged carbon atoms can slide over one another, as the layers are held together by van der Waals forces of attraction.

Melting and boiling points

Diamond and graphite: Very high. A large amount of energy is required to break numerous, strong covalent bonds between carbon atoms.

Electrical conductivity

Diamond: Insulator. Mobile electrons are absent. All four valence electrons are used in covalent bonds.

Graphite: Conductor. Three out of four valence electrons are used for covalent bonding with other carbon atoms. Remaining valence electrons can be delocalised across the planes of carbon atoms