Rutherford atomic model
In many ways, Rutherford’s atomic model is regarded as the classical model of the atom , even though it is no longer regarded as an accurate representation today. Rutherford’s model shows that an atom is largely a vacuum space , with electrons that are orbiting a core fixed positively charged paths predictable and configured .
What is the Rutherford model?
Rutherford’s atomic model is the model that suggests that the atom looks very similar to that of a planetary system and for this reason it was called a planetary model or a nucleated atom model .
This model of the atom was developed by Ernest Rutherford , a New Zealand scientist working at the University of Manchester in England in the early 20th century. Rutherford spent most of his academic career researching aspects of radioactivity and, in 1908, he won the Nobel Prize for his discoveries related to radioactivity. It was after this that Rutherford began to develop his model of the atom.
- What is Rutherford’s atomic model?
- Rutherford’s atomic model postulates
- What problems does Rutherford’s atomic model present?
What is Rutherford’s atomic model?
Thomson model consisted of the presentation of an atom static and solid . The model that was proposed by Rutherford explained that the positive charge that an atom had is concentrated in a stationary nucleus of great mass, and that electrons with negative charge move in orbits that were around the nucleus, which were united by the electrical attraction that exists between opposite charges.
The main characteristics of Rutherford’s atomic model are the following:
- The theory considers that the atom is divided into a nucleus and a crust .
- His theory said that the atom is practically hollow .
- It did not explain atomic spectra .
- His atomic model suggests that the atom is very similar to a planetary system .
- According to this model, electrons revolve around the nucleus in a similar way to planets revolving around the Sun.
- It is considered as the basis of atomic theory.
Rutherford’s atomic model postulates
Rutherford’s Atomic Model postulates the following:
- The atom is made up of two regions: a shell and a nucleus .
- In the shell of the atom we can find electrons that are spinning around the nucleus at high speed.
- The nucleus is a small region that is located in the center of the atom which is the one with the positive charge.
- The nucleus has practically the entire mass of the atom .
His most important contribution was that he postulated that the atom was made up of a nucleus in which almost all of the atomic mass could be found and that all the charge in the nucleus was positive. He also contributed the theory that electrons revolve around the nucleus.
In order to make an analysis regarding the structure of the atom, Rutherford designed an experiment that consisted of bombarding a fine gold foil with alpha particles. If Thomson’s atomic model was correct then the particle beam should pass through the sheet without undergoing significant deflections that could affect its trajectory . Rutherford was able to observe that a high percentage of particles managed to pass the sheet without undergoing an appreciable deflection, but he was also able to observe that there were a certain number of them that ended up being deflected significantly, sometimes under diffusion angles.they were even greater than 90 degrees. Such deviations could not occur if Thomson’s model were correct.
What problems does Rutherford’s atomic model present?
The two main problems that the theory presented were that Rutherford assumed that the electrons were rotating around the nucleus because that way they would counteract the force that pulled them towards the nucleus, but this led, according to Maxwell’s laws of electromagnetism to an emission of energy , since every particle with acceleration had to emit it, which in turn would cause the electron to fall to the nucleus .
On the other hand, Rutherford’s atomic model was not able to explain the appearance of the emission and absorption spectra observed in some elements such as hydrogen. It could then be verified that for some values there were dark fringes in the emission spectra, and that for the same frequencies lines were observed in the emission spectra.
Its main significance was that first proposed the existence of a nucleus in the atom theory was considered essential to explain the results of the concentrations of load in the center of the atom. The results of his model and of his experiments made it possible to get to know and calculate that the atomic radius is ten thousand times greater than the nucleus of the atom and therefore that the interior of the atom is basically empty.
It was then the first theory that told us about the existence of the nucleus and the crust found in it, the existence of electrons and how each atom was made up of a nucleus that should have a positive charge , a fairly small radius. where the mass of the atom was concentrated and a crust that was formed by a cloud of electrons that were orbiting around the nucleus.