Question

Explain how effective nuclear charge is related with stability of the orbital.

Answer 1

• In a multi-electron atom, in addition to the electrostatic attractive force between the electron and nucleus, there exists a repulsive force among the electrons. 
• These two forces are operating in the opposite direction. This results in the decrease in the nuclear force of attraction on electron. 
• The net charge experienced by the electron is called effective nuclear charge. 
• The effective nuclear charge depends on the shape of the orbitals and it decreases with increase in azimuthal quantum number l. 
• The order of the effective nuclear charge felt by a electron in an orbital within the given shell is s > p > d > f.
• Greater the effective nuclear charge, greater is the stability of the orbital. Hence, within a given energy level, the energy of the orbitals are in the following order s < p < d < f.