Ionization Energy Made Easy! Inorganic CHEM – 1.16

The course I’m teaching is a distilled version of the material covered in the following textbooks, which I highly reccommend:

Inorganic Chemistry: https://amzn.to/4cW8v82

Chemistry, 5th addtion: https://amzn.to/3W0EQDS

This video explains Ionization Energy. Please note that the information in this video may not always be accurate or up-to-date due to new discoveries. There may also be overlooked mistakes. Therefore, only use this video as an additional resource to enhance your understanding.

Steps to Calculate 𝑍eff:
1. Write the Electron Configuration: Identify the electron configuration of the element.

2. Group Electrons by Shells and Subshells: Arrange the electrons in groups according to their shells (n) and subshells (s, p, d, f).

3. Apply Slater’s Rules:
– Electrons in the same group (same n and l) shield each other by 0.35 each (except 1s, which is 0.30).
– Electrons in n-1 shell shield by 0.85 each.
– Electrons in shells n-2 or lower shield by 1.00 each.

4.Calculate Shielding Constant (S): Sum the contributions from all electrons that shield the electron of interest.

5. Calculate 𝑍eff: 𝑍eff = 𝑍 − 𝑆, where 𝑍 is the atomic number and 𝑆 is the shielding constant.

Example: Calculate 𝑍eff for the 3s electron in Sodium (Na)

1. Electron Configuration of Na: 1s2, 2s2, 2p6, 3s1

2. Group Electrons:
– (1s2)
– (2s2, 2p6)
– (3s1)

3.Apply Slater’s Rules:
– Electrons in the same group (3s): No shielding, as there are no other electrons in the 3s subshell.
– Electrons in the n-1 shell (2s and 2p): 8×0.85 =6.80
– Electrons in the n-2 shell (1s): 2×1.00=2.00

4. Calculate Shielding Constant (S):
– S = 6.80+2.00 = 8.80

5. Calculate Zeff
– Z=11 (atomic number of Na)
– Zeff =11−8.80=2.20

Therefore, the effective nuclear charge (Zeff) for the 3s electron in sodium is 2.20.