Question

The size of isoelectronic species — F⁻, Ne and Na⁺ is affected by (a) nuclear charge (Z) (b) valence principal quantum number (n) (c) electron-electron interaction in the outer orbitals (d) none of the factors because their size is the same.

Answer 1

As F⁻ , Ne , Na⁺ are Iso-Electronic Species :

The Size of each of these Atoms depends upon the Number of Protons the respective Atom contains. The Atom which contains more number of Protons has smaller Size compared to the other Iso-Electronic species.

Because : Higher Positive charge (Nuclear Charge - Z) pulls the Electronic orbits to towards itself. In this Process the Atom with more number of Protons, Size Shrinks.

So, The Size of Iso-Electronic Species : F⁻ , Ne , Na⁺ is affected by Nuclear Charge (Z)

Option (a) is the Answer