Which of the following elements has the highest effective nuclear charge?

Correct option is C

​The correct answer is (c) F

Explanation:

• Fluorine (Z=9) has 9 protons and 9 electrons.
• Its effective nuclear charge is quite high compared to other elements because it has a relatively small atomic size, with only one electron shell being shielded by the core electrons.
• The effective nuclear charge for fluorine is around 7 (due to partial shielding by the inner electrons).

Information Booster:

• The effective nuclear charge refers to the net positive charge experienced by an electron in an atom.
• It is the result of the nuclear charge (number of protons in the nucleus) minus the shielding effect of inner electrons.
  

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