Question

The metal which has the greatest tendency for the reaction $M_{\left(g\right)}\to M_{aq}^{+}+e^{-}$ is:

• A. $Li$
• B. $Na$
• C. $K$
• D. $Rb$

Answer 1

Answer: (D)

$Rb$

Among alkali metals, Rb has the lowest ionization energy. Hence it has maximum tendency to lose an electron and form a cation.

Hence Rb has greatest tendency for the reaction $M_{\left(g\right)}\stackrel{}{\to }{M_{aq}}^{+}+e^{-}$.

Note; In the group of alkali metals, the ionization energy decreases on moving from top to bottom.

Hence, the correct option is $\text{D}$