Calculate the effective nuclear charge of sodium
The effective nuclear charge of an atom is a measure of the positive charge experienced by an electron in that atom.
It is equal to the actual nuclear charge (number of protons in the nucleus) minus the screening or shielding effect of the inner electrons.
Sodium has an atomic number of 11, which means it has 11 protons in its nucleus.
The electronic configuration of sodium is 1s²2s²2p⁶3s¹.
To calculate the effective nuclear charge (Zeff) for sodium, we need to consider the shielding effect of the inner electrons. The inner core electrons (1s²2s²2p⁶) shield the outer electron (3s¹).
The shielding effect of each inner electron is approximately equal to 1, regardless of the number of protons in the nucleus. Therefore, the total shielding effect of the 10 inner electrons is approximately equal to 10.
So, the effective nuclear charge (Zeff) for sodium is:
Zeff = Number of protons - Shielding effect of inner electrons
Zeff = 11 - 10
Zeff = 1
Therefore, the effective nuclear charge of sodium is 1.