(Solved): b) The electronic configuration of the alkali metal francium is given by [Rn]7s. The first ionisa ...

b) The electronic configuration of the alkali metal francium is given by $$[\mathrm{Rn}]7\mathrm{s}$$. The first ionisation potential is equal to $$4.07\mathrm{eV}$$, and the average wavelength of the $$8\mathrm{p}?7\mathrm{s}$$ transition is $$428\mathrm{nm}$$. Find the minimum value of $$?(2)$$ that would allow the $$8p?6d$$ transition to be observable in emission.