The total number of molecular orbitals formed from $$2s$$ and $$2p$$ atomic orbitals of a diatomic molecule is _______.

In a diatomic molecule, molecular orbitals are formed by the linear combination of atomic orbitals (LCAO). Each pair of atomic orbitals (one from each atom) combines to form two molecular orbitals — one bonding and one antibonding.

From the 2s atomic orbitals:

Each atom contributes one 2s orbital. These two 2s orbitals combine to form:

1. $$\sigma_{2s}$$ (bonding)

2. $$\sigma^*_{2s}$$ (antibonding)

That gives 2 molecular orbitals.

From the 2p atomic orbitals:

Each atom contributes three 2p orbitals ($$2p_x$$, $$2p_y$$, $$2p_z$$). These six atomic orbitals (3 from each atom) combine to form:

1. $$\sigma_{2p_z}$$ (bonding)

2. $$\sigma^*_{2p_z}$$ (antibonding)

3. $$\pi_{2p_x}$$ (bonding)

4. $$\pi^*_{2p_x}$$ (antibonding)

5. $$\pi_{2p_y}$$ (bonding)

6. $$\pi^*_{2p_y}$$ (antibonding)

That gives 6 molecular orbitals.

Total molecular orbitals = 2 + 6 = 8.

The answer is 8.