Neil Bohr’s model of

atom

In Rutherford’s model, the exact location of the electrons outside the nucleus was not determined. It just stated that they were held in place outside the nucleus due to the attraction between the positive and the negative electron. The exact location of electrons at the edge of the atom could not be determined using the model.

In 1913, Neils Bohr made an improvement on Rutherford’s model. In his model, he placed each electron on a specific energy level. This electron moved in definite orbits around the nucleus just like the movement of planets around the Sun in the solar system. These orbits or energy levels were located at certain distances around the nucleus.

Bohr proposed that electrons are restricted to certain fixed (quantized) orbits. An electron can jump, suddenly, between these orbits by observing or emitting a photon with the appropriate precise wavelength.

The wave model of atom

The Bohr model was sufficient enough to explain the structure and behavior of simple atoms like hydrogen. But it could not explain the behavior of more complex atoms.

The most recent atomic model was based on the principle of wave mechanics which involves complex mathematical equations and are quite complicated. The theory of wave mechanics explain that the movement of electrons about an atom has no definite path. It is therefore impossible to determine the exact location of an electron. Scientists can only predict the probable location of electron. It is based how much energy it has.

Wave atomic model

Activity 3:Materials needed:

Cardboard ScissorsColored papersColored pencilsStringCotton

Neutron

Electron

Proton

Electron orbits

Bohr’s atomic model Wave atomic model

…..THE END…..Thanks you….

BY: JOSEPH H. BULTRON

JR. GRADE 11 - AGUINALDO