Question

The oxidation number of carbon in diamond is:

• A. Zero
• B. $+4$
• C. $-4$
• D. $+2$

Answer 1

The correct option is A

Zero

The explanation for the correct option

(A) zero

Oxidation number

• “Oxidation number denotes the oxidation state of an element in a compound ascertained according to a set of rules formulated on the basis that electron pair in a covalent bond belongs entirely to a more electronegative element.”

The oxidation number of carbon in the diamond

• Carbon exhibits many allotropic forms. Diamond and graphite are two well-known crystalline forms of carbon.
• Each carbon atom in a diamond undergoes ${\mathrm{sp}}^3$ hybridisation and is bonded to four other carbon atoms in a tetrahedral fashion.
• The oxidation number of an element in its free states is zero.
• Diamond is elemental carbon.
• So, the oxidation state of carbon in diamonds is zero.

The explanation for incorrect option

The oxidation state of carbon in diamonds is zero. Hence, the options (B), (C), and (D) are incorrect.

Hence, option (A) is correct. The oxidation number of carbon in diamonds is zero.