Rutherford's Atomic Model PDF

## Rutherford's Atomic Model Rutherford concluded the following from his experiments and observations: - The atom is primarily empty space because most alpha particles pass through it. - The positive charge and mass of an atom are concentrated in the center of the atom, called the nucleus. - Elect...

## Rutherford's Atomic Model Rutherford concluded the following from his experiments and observations: - The atom is primarily empty space because most alpha particles pass through it. - The positive charge and mass of an atom are concentrated in the center of the atom, called the nucleus. - Electrons are located outside the nucleus at a relatively large distance and revolve around it like planets around the sun. ### Rutherford's Model Consists of Two Parts: 1. **Nucleus:** - A small positively charged part of the atom, located at the center. - Contains neutrons and protons. - Responsible for almost the entire mass of the atom. 2. **Extra Nuclear Part:** - The empty space outside the nucleus. - Electrons revolve around the nucleus in fixed paths called orbits or shells. - Responsible for the atom’s volume. This model is comparable to the solar system, with the nucleus representing the sun and the orbiting electrons representing planets. ### Important Fundamental Particles: - Electrons, protons, and neutrons are the most important particles found in atoms (except hydrogen). - Hydrogen has only one proton and one electron. - Since atoms are electrically neutral, they have the same number of electrons and protons. The charge of a proton is equal and opposite to the charge of an electron. ### Drawbacks of Rutherford's Model: - Although Rutherford's model successfully explained the scattering of alpha particles, it failed to explain the stability of the atom. **According to Rutherford's model:** - The electrons orbit the nucleus in a circular path. The attractive force between the nucleus and the electrons is balanced by the electrons' centrifugal force. **According to electromagnetic theory:** - A rotating electron emits radiation, which causes a loss of energy. - The loss of energy disrupts the equilibrium between the nucleus and the electron. - To regain equilibrium, the electron gradually approaches the nucleus, continuously emitting radiation until it loses all its energy and falls into the nucleus. This makes the atom unstable. **Therefore, Rutherford’s model predicts that a continuous spectrum should be emitted by an atom when electrons rotate continuously, but a discontinuous line spectrum is actually observed.**