For any student, it’s important to have the right understanding of atoms. The Rutherford model is no longer very accurate, but it was revolutionary in the past. You should learn more about its definition, interesting features, and development of atom models. In many ways, it’s a classic one because it shows that any atom is almost an empty space that contains positively charged nucleus orbited by electrons and predictable paths.
As its name suggests, this atom model was developed by Rutherford, who was born in New Zealand and worked in one university in Manchester. Keep in mind that he spent a big part of his career on researching different radioactivity aspects and he even succeeded to win the Nobel Prize for discoveries in this field.
They were first discovered by Democritus, a famous Greek philosopher, but this concept was lost until John Dalton stated that everything consisted of very small indivisible particles, atoms. He offered quite a simple model of atoms that was the only one until Thomson discovered that they contain electrons, negatively charged particles. This is when most scientists believed that atoms consisted of electrons spread over their positively charged matrix. The structure of atoms offered by Thomson is also called a plum pudding model. The one suggested by Dalton depicted a solid, tiny, and indivisible sphere.
Everything started when he conducted a well-known gold foil experiment with his colleague, Hans Geiger, and this is was a starting point for developing the Rutherford model. They bombarded a gold foil with alpha particles that were positively charged because scientists expected them to travel through this piece of foil. However, many of these particles simply ricocheted off it, thus suggesting that there was something positive that they were colliding with. Rutherford and his colleague called this positive force as the nucleus, so the famous Rutherford model was developed based on the data gathered during this experiment.
You should understand that there are certain problems associated with it. The main one is that some particle physicists and chemists discovered that the behavior of electrons was more complex than the one depicted in this model. For example, electrons don’t travel in set paths, their location around the nucleus may change based on their energy, and their speed is inconsistent. This is how the Rutherford model stopped to be the most accurate one to depict electrons as something that travels only in straight paths. Physics started to represent them by specific electron clouds suggesting where electrons might be at a particular moment of time. Take into account that this electron cloud model is the most updated one nowadays.
As you already know, the planetary model of atoms offered by Rutherford describes any atom as a dense, tiny, and positively charged core or nucleus where the entire mass is concentrated, and around which negative and light constituents or electrons circulate, just like planets revolve around the Sun. The Rutherford model displaced the plum pudding one offered by Thomson, but it was later superseded by the atomic model suggested by Bohr that incorporated the early quantum theory.
The experiment with a gold foil helped Rutherford to come with a conclusion that the plum pudding model wasn’t correct. His new model of an atom contained new features of quite a high central charge concentrated into a tiny small volume compared to the rest of atoms, and this region was called its nucleus based on the results of this experiment.
As a good student, you should learn more about the experimental basis of developing the Rutherford model. This famous scientist overturned the model of atoms developed by Thomson in 1911 during his widely known gold foil experiment that demonstrated that every atom had a heavy and tiny nucleus. He used the alpha particles of radioactive elements as probes to the hidden world of atomic structures. If the concept offered by Thomson was correct, the beam would pass through a gold foil, but most of it went through it.
This is what allowed Rutherford to present his unique model for a subatomic structure as his valuable interpretation of unexpected experimental results. If you take a look at it, you will see that atoms are made up of central charges or nucleus and surrounded by a cloud of electrons that keep orbiting.
When it comes to energetic consideration of how far given particles that have a known speed can penetrate toward this central charge, Rutherford succeeded to determine the radius of a gold foil central charge. Remember that the Rutherford model described a great deal of atomic charges and mass concentrated to quite a small core, but the main drawback is that it didn’t attribute any structure to remaining electrons and atomic mass. Besides, it mentioned the atomic model suggested by Hantaro Nagaoka where electrons were arranged in 1 or more things with a metaphorical structure of Saturn stable rings. It’s interesting that the model offered by Thomson also has such rings for orbiting electrons.
The main thing that should be remembered about the Rutherford model is that the electron cloud of atoms doesn’t have any impact on scattering alpha particles. The most of their positive charge is concentrated in a very tiny volume right at the center of atoms called the nucleus. Take into account that the magnitude of this type of charge is proportional to the atomic mass of a given atom. This remaining mass is known to be attributed to neutrons these days. One of the most important details is that this charge and concentrated central mass are responsible for deflecting both beta and alpha particles.
When dealing with the mass of such heavy atoms as the ones in gold, don’t forget that they’re mostly concentrated in a central charge area. That’s because relevant calculations prove that this mass is not moved or deflected by alpha particles with a high speed. They have quite a high momentum compared to electrons, but this rule can’t be applied to heavy atoms as wholes. Take this aspect into consideration when learning everything about the Rutherford model.
Your knowledge of this subject is not complete if you don’t know anything about the contribution of this atomic model suggested by Rutherford to modern science. After his incredible discovery, many other scientists started to understand that atoms are not single particles because they are made of smaller subatomic particles. There were multiple subsequent studies and tests that determined a specific atomic structure that led to the gold foil experiment of Rutherford.
Other scientists succeeded to discover that an atom has the nucleus that is positively charged and located in its center, while electrons are smaller. In addition, they also determined an expected number of electrons in atoms by using X-rays, and the Rutherford model contributed to it too. When X-rays pass through atoms, some of them are scattered, while the rest passes through atoms. Another important fact is that such rays lose their intensity because of scattering electrons, and this means that a number of electrons in a given atom is easy to estimate by finding the rate of this intensity decrease. Be sure to use this knowledge when completing relevant academic assignments.