Question 9: How many bonding pair are present in carbon(IV) oxide molecule?

• Carbon (C) has 4 valence electrons.
• Oxygen (O) has 6 valence electrons.
• Total valence electrons = $4 + (2 \times 6) = 4 + 12 = 16$ electrons.

Carbon is the central atom, bonded to two oxygen atoms: O - C - O.

Place a single bond between the central carbon and each oxygen atom. This uses $2 \times 2 = 4$ electrons.
Remaining electrons = $16 - 4 = 12$ electrons.

Each oxygen needs 6 more electrons to complete its octet.
$\ddot{\text{O}} - \text{C} - \ddot{\text{O}}$
This uses $2 \times 6 = 12$ electrons.
Remaining electrons = $12 - 12 = 0$ electrons.

At this point, each oxygen has an octet (2 from bond + 6 lone pair), but carbon only has 4 electrons (2 from each single bond).

To satisfy carbon's octet, move one lone pair from each oxygen atom to form a double bond with the carbon atom.
$\ddot{\text{O}} = \text{C} = \ddot{\text{O}}$

• Each oxygen atom now has 4 electrons from the double bond and 4 lone pair electrons, totaling 8 electrons.
• The carbon atom has 4 electrons from each double bond, totaling 8 electrons. All atoms have complete octets.

• There is a double bond between the left oxygen and carbon. A double bond consists of 2 bonding pairs.
• There is a double bond between the right oxygen and carbon. A double bond consists of 2 bonding pairs.
• Total bonding pairs = $2 + 2 = 4$.

Therefore, there are 4 bonding pairs in a carbon(IV) oxide molecule.

The correct option is B.