Write Bohr's postulates for the hydrogen atom model.

Bohr's three postulates are as follows : (i) An electron in an atom could revolve in certain stable orbits without the emission of radiant energy. Hence, each atom has definite stable states in which it exists, and each possible state has a definite energy. These are called the stationary states of the atom. (ii) The electron revolves around the nucleus in those orbits for which the angular momentum is some integral multiple of h 2 π where h is Planck's constant. (iii) An electron might make a transition from one of the specified non-radiating orbits to another of lower energy. When it does so, a photon is emitted having energy equal to the energy difference between the initial and final states.

Draw the diagram representing the schematic arrangement of Geiger Marsden experimental set up of alpha particle scattering experiment.

The experimental set up of alpha-particle scattering experiment is: 1) Most of the alpha particles pass straight through the gold foil. It means they do not suffer any collision with gold atoms. 2) Only about 0 . 14 % of incident α -particles scatter by more than 1 ° . 3) About one α -particle in every 8000 α -particles deflect by more than 90 ° . This led to Rutherford postulate, that the entire positive charge of the atom must be concentrated in a tiny central core of the atom. This tiny central core of each atom was called the atomic nucleus.

E M B I B E

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 12 - Atoms>Karnataka Board-2019>Q 3

EASY

12th Karnataka Board

IMPORTANT

Earn 100

Write the expression for energy of an electron in electron orbit of hydrogen atom.

Important Questions on Atoms

EASY

12th Karnataka Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 12 - Atoms>Karnataka Board-2019>Q 4

Write the three postulates of Bohr’s atomic model.

HARD

12th Karnataka Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR PHYSICS>Chapter 12 - Atoms>Karnataka Board-2020>Q 5

Using Bohr's postulates, derive the expression for the radius of $n^{t h}$ stationary orbit of the electron in a hydrogen atom. Hence, write the expression for Bohr radius.

Learn and Prepare for any exam you want !

|

|

|

|

|

|

|

|