﻿ In Bohr’s model of hydrogen atom, the radius of the first electron orbit is 0.53 Å. What will be the radius of the third orbit? What of the first orbit of singly-ionised helium atom? : Kaysons Education

# In Bohr’s Model Of Hydrogen Atom, The Radius Of The First Electron Orbit Is 0.53 Å. What Will Be The Radius Of The Third Orbit? What Of The First Orbit Of Singly-ionised Helium Atom?

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## Question

### Solution

Correct option is

0.265 Å

The radius of the nth Bohr orbit is given by

From this, we have

For hydrogen Z = 1 and for helium Z = 2.

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