Question

Chloride ion and potassium ion are isoelectronic. Then –

• A. Their sizes are same
• B. Cl^– ion is bigger than K⁺ ion
• C. K⁺ ion is relatively bigger
• D. Their sizes depend on other cation and anion

Answer 1

Answer: (B)

Cl^– ion is bigger than K⁺ ion

Answer 2

Cl^– K⁺

Zeff, = $\frac{Z}{e}$ = $\frac{17}{18}$ $\frac { 19 } { 18 }$ $\overset{\rightarrow}{\quad\begin{matrix} Zeff \uparrow \\ Size \downarrow \end{matrix}\quad}$

\ Order of size Cl^– > K⁺