JEE Advanced · 2007 · 08 Apr 2007 · Paper 2 · s-Block Elements

Statement-1 is true: alkali metals do dissolve in liquid ammonia to give blue solutions. Statement-2 is also true: the metal atoms ionize to form solvated cations ${\left[\mathrm{M}{\left({\mathrm{NH}}_3\right)}_n\right]}^{+}$. However, Statement-2 is NOT a correct explanation for Statement-1 because the blue color is due to solvated electrons $\left[e^{-}({\mathrm{NH}}_3{)}_n\right]$, not the solvated metal cations. The electrons released during ionization are responsible for the characteristic blue color.