Question

If the radius of first Bohr orbit is x pm, then the
radius of the third orbit would be​

Answer 1

The radii of the n

th

stationary states of Hydrogen and Hydrogen like atom is given by:

r

n

=a

0

Z

n

2

where a

0

=52.9 pm,n=n

th

Bohr orbit, Z=atomic number .

Given: The radius of the first stationary state i.e Bohr orbit=x pm

r

1

=a

0

Z

1

2

=x pm

or x=a

0

Z

1

Z=

x

a

0

Radius of third orbit: r

3

=a

0

Z

3

2

substitute the above relation:

Radius of third orbit: r

3

=a

0

a

0

9x

=9x pm