Which of the following best describes electron shielding in atoms?

• A. The process by which electrons are removed from an atom during ionization.
• B. The increase in nuclear charge experienced by electrons as atomic number increases.
• C. The attraction between valence electrons and the nucleus in a neutral atom.
• D. The reduction in effective nuclear charge on the outer electrons due to repulsion by inner electrons.

Answer: (D)

Verified step by step guidance

1. Understand that electron shielding refers to the effect inner electrons have on reducing the attraction between the nucleus and the outer (valence) electrons.
2. Recognize that inner electrons repel outer electrons, which decreases the effective nuclear charge felt by the outer electrons.
3. Recall that effective nuclear charge (\(Z_{eff}\)) is the net positive charge experienced by an electron in a multi-electron atom, calculated as \(Z_{eff} = Z - S\), where \(Z\) is the atomic number and \(S\) is the shielding constant.
4. Note that electron shielding does not involve removing electrons (ionization) or increasing nuclear charge, but rather the reduction of nuclear attraction due to electron-electron repulsions.
5. Conclude that the best description of electron shielding is the reduction in effective nuclear charge on the outer electrons caused by repulsion from inner electrons.