Question

Polarising action of $C{d}^{2+}$ an anions is stronger than that of $C{a}^{2+}$ because:

• A. the charges of the ions are same
• B. their radii are same ($C{a}^{2+}$ = 0.104 nm, $C{d}^{2+}=0.099$ nm)
• C. the $C{a}^{2+}$ ion has a noble-gas electron configuration, and the $C{d}^{2+}$ ion has an 18 electron configuration in its outer shell
• D. all of the above

Answer 1

Answer: (C)

the $C{a}^{2+}$ ion has a noble-gas electron configuration, and the $C{d}^{2+}$ ion has an 18 electron configuration in its outer shell

Cations with 18 electrons shall have greater polarising power than the cation with 8 electron shell.

the linear electron has a poor shielding effect on the nucleus and thus E.N of the 16-electron shell is increased.

Cadmium ion $\left({Cd}^{2+}\right)$ has atronger polarsing power than $\left({Ca}^{2+}\right)$ due to the above stated fact $\left({Cd}^{2+}\right)$ has 18 electrons configration where as $\left({Cd}^{2+}\right)$ ion has an noble gas configration ( 8 electron shell).