E=hv or v=hE For H atom, EΔE=n2−21.76×10−19 J atm−1=−21.76×10−19(421−121) v=20.40×10−19 J atm−1=6.625×10−3420.40×10−19=3.079×1015 s−1.
The frequency radiation emitted when the electron falls from n=4 to n=1 in a hydrogen atom will be (Given ionization energy of H=2.18×10−18 Jatom−1 and h =6.625×10−34Js) :
Held on 30 Apr 2004 · Verified 9 Jul 2026.
1.54×1015 s−1
1.03×1015 s−1
3.08×1015 s−1
2.00×1015 s−1
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