In 1911 Rutherford experimented to know about arrangements of sub-atomic particles such as electrons and protons in an atom.
Rutherford’s Gold Foil Experiment
- First of all, Rutherford took a gold foil of about 4×10-5cm and bombarded alpha particles on it.
- Alpha particles are helium nuclei with two protons and two neutrons present together.
- The alpha particles that were used in this experiment were obtained from the disintegration of Polonium
- The majority of these particles passed through the foil undeflected so Rutherford hypothesized that most of the space in an atom is empty.
- Because some of the alpha particles were somewhat deflected by the gold sheet, the positive charge in an atom is not spread evenly. An atom’s positive charge is confined to a very small volume.
- Only a handful of the alpha particles were deflected back, meaning that their angles of deflection were only about 180 degrees. Consequently, the positively charged particles in an atom only occupy a very tiny portion of the atom’s overall volume.
Rutherford Atomic Model Diagram
Rutherford Scattering Experiment Conclusion
- An atom’s positive charge and the majority of its mass are packed into a very tiny volume. He referred to this part of the atom as the nucleus.
- According to Rutherford’s theory, an atom’s nucleus is surrounded by electrons that are negatively charged. He also asserted that the electrons that surround the nucleus travel in a circular pattern at extremely high speeds. He named these cyclical routes “orbits.”
- A strong electrostatic force of attraction holds the negatively charged electrons also the positively charged mass that makes up the nucleus together.
Defects of Rutherford Atomic Model
- Despite being founded on experimental findings, the Rutherford atomic model proved unable to explain several phenomena.
- According to classical physics, an electron being a charged particle an electron should emit energy continuously when it is revolving around the nucleus. So that loses all of its energy and ultimately spirals into the nucleus.
- If a revolving electron emits energy continuously, then the spectrum obtained should be continuous; instead, a line spectrum is obtained.
Check out -> Structure of Atom MCQs
Continue Reading -> Bohr Model of atom
Frequently Asked Questions -FAQs
What does Rutherford’s model explain?
It explains that an atom is made up of a relatively small mass of an atom, known as the nucleus, where all of the atom’s mass is concentrated and where the electrons are free to move around easily.
What is Rutherford’s atomic model called?
The “Rutherford nuclear atom” and “Rutherford Planetary Model” were other names for the Rutherford atomic model.
Why did Rutherford’s model of an atom fail?
The stability of electrons moving in a circular direction could not be explained by Rutherford’s atomic model. He claimed that while particles in motion would experience acceleration and produce energy radiation, electrons move in a circular manner around the nucleus. Electrons should eventually become less energetic and fall into the nucleus.
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