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AP EAMCET20227 Jul 2022Morning ShiftChemistryStructure of AtomActual

The ratio of radii of second orbit of hydrogen atom to fourth orbit of He ⁺ ion is

Options

  1. A1: 4
  2. B2: 1
  3. C1: 2
  4. D2: 3

Correct answer

C. 1: 2

Step-by-step solution

For hydrogen and hydrogen like atoms r_n=n^2 / Z where, r_n is radius of n th orbit of revolution of electron, Z is the atomic number. For hydrogen atom, Z=1 . Hence, radius of second orbit is r₂= (2)^2 1 =4 For helium atom, Z=2 . Hence, radius of fourth orbit is r₄= (4)^2 2 =8 Therefore, r₂ r₄ = 4 8 = 1 2 1: 2

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