Option 3 : Size of the orbital

CT 1: हिन्दी (आदिकाल)

5711

10 Questions
40 Marks
10 Mins

__Concept:__

Bohr's atomic model.

- The electrons revolve around the nucleus in circular orbits with discrete energy, i.e, the energy is quantized.
- The radius of the orbits is also fixed and depends on the principal quantum number n.
- When electrons are supplied with energy, they jump to higher orbitals.
- The angular momentum of the electrons is quantized and given by

\(mvr = \frac{{nh}}{{2\pi }}\).

- The frequency of light ν required to transition of an electron that differs in energy by

\(\Delta E\;isequal\;to = \frac{{\Delta E}}{h} = \frac{{hν '' - hν '}}{h} = ν \;\;\) where hν'' and hν' is the energy of higher and lower orbitals respectively.

- The Energy of an electron in a stationary orbit is given by:

\(E_n = - R_H\frac{{Z^2}}{{n^2}}\)

__Explanation:__

The principal quantum number n and size of orbitals :

- This quantum number designated as ' n ' gives the number of major energy shells or orbit to which an electron belongs.
- It can have any positive whole number values excluding zero.
- The number ' n ' thus can have infinite positive values.
- The value of ' n ' represents the shells that are designated by capital letters K, L, M, N.
- The principal quantum number determines the distance of the electron from the nucleus.
- A lower value of ' n ' represents that the electron is nearer to the nucleus.
- On increasing the value of ' n ', the size of the orbital will also increase then.

Thus, ' n ' represents the size of the orbits.

Hence, the Principal quantum number determines the **size of the orbital.**

__Additional Information__