Question on: JAMB Chemistry - 2020

The electronic configuration provided is 1s² 2s² 2p⁶ 3s² 3p³. 1. **Focus on the outermost shell:** The outermost shell is the 3rd shell, which contains 3s² and 3p³. We only need to consider the 3p orbitals since the 3s orbital is completely filled and does not contain unpaired electrons. 2. **3p orbital:** The 3p subshell has three orbitals, each of which can hold a maximum of two electrons. 3. **Filling the 3p orbitals:** The 3p³ configuration means there are three electrons to be distributed in the 3p orbitals. Following Hund's rule, these electrons will singly occupy each of the three 3p orbitals before pairing up. * 3p: _↑_ _↑_ _↑_ 4. **Unpaired electrons:** From the distribution of electrons in the 3p orbitals, there are three unpaired electrons.