If the shortest wave - length of a spectral line in Lyman series for He+ is 'x', then what will be the largest wave length of a spectral line in Balmer series of Li2+
16x5
For the shortest wave length of spectral line in He+ the transition should be from n∞→n1
Thus 1λmin=RH.Z2n21
or 1x=RH.41[For He+;Z=2,λmin]
or RH=14x ...(i)
For the largest wave length in Balmer series of Li2+ the transition occurs from n2=3 to n2=2 and in such a case we have
1λmax=RH.Z2[1(n2)1−1n22]
or 1λmax=RH.(3)2[1(2)2−1(3)2]
or 1λmax=14x×[14−19] [RH=14x]
or 1λmax=94x(9−436)
or 1λmax=94x×536
or 1λmax=516x
or 1λmax=16x5