Practice question · Numerical answer
For a valence electron of silicon (), the shielding constant is by Slater’s rules. Compute the effective nuclear charge, to two decimal places.
Hints
- Effective nuclear charge is the actual charge minus what is screened.
- Compute 14 - 9.85.
Show the answer
4.15 (answers within ±0.03 count)
Why
. The valence electron feels roughly a pull rather than the full , which is why silicon is far larger than its nuclear charge alone would suggest.
Practise Periodic Properties
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