For Li²⁺ (Z=3): From n2+n1=4 and n2−n1=2, we get n2=3, n1=1
Using Bohr wavelength formula: λ1=RZ2(n121−n221)
λ1=1.097×107×9×(1−91)=9.873×107×98
λ1=8.776×107 m⁻¹
λ=1.14×10−6 cm
JEE Main 2026 — Chemistry Physical Chemistry
The wavelength of spectral line obtained in the spectrum of Li2+ ion, when the transition takes place between two levels whose sum is 4 and difference is 2, is
Held on 24 Jan 2026 · Verified 6 Jul 2026.
1.14×10−7 cm
1.14×10−6 cm
2.28×10−7 cm
2.28×10−6 cm
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