Rutherford model

src: i.ytimg.com

The Rutherford model is an atom model designed by Ernest Rutherford. Rutherford directed the famous experiments of Geiger-Marsden in 1909 suggesting, based on the Rutherford analysis of 1911, that J. J. Thomson's plum pudding model of the atom was incorrect. Rutherford's new model for atoms, based on experimental results, contains new features of relatively high central charges concentrated into very small volumes compared to the rest of the atoms and with this central volume also containing most of the atomic mass. of atoms. This region will be known as the "nucleus" of atoms.

Video Rutherford model

Experimental basis for model

Rutherford overturned Thomson's model in 1911 with his famous gold foil experiment in which he showed that atoms have small, heavy nuclei. Rutherford designed an experiment to use alpha particles emitted by radioactive elements as probes into the unseen world of atomic structures. If Thomson is right, the light will go right through the gold foil. Most of the beams penetrate the foil, but little is reflected.

Rutherford presented his own physical model for subatomic structures, as interpretations for unexpected experimental results. In it, the atom consists of a central charge (this is a modern atomic nucleus, though Rutherford does not use the term "nucleus" in his paper) surrounded by a cloud of electrons (which may) orbit. In this May 1911 paper, Rutherford only binds himself to the tiny central region of a very high positive or negative charge in the atom.

For concrete, consider part of the high speed? particles through atoms that have a positive central charge N e , and are surrounded by an electron's N compensating charge.

From the really energetic consideration of how far the known particles of velocity will be able to penetrate toward the 100 Â ° center load, Rutherford is able to calculate that the central radius of the gold charge will need less (how little can not be told) of 3, 4 ÃÆ'â € "10 ^-14 meter. This in a gold atom known as 10 ^-10 meter or more in radius - a very surprising finding, because it implies a strong central charge of less than 1/3000 the diameter of the atom.

The Rutherford model serves to concentrate many atomic and mass charges to a very small nucleus, but does not associate any structure with the remaining electrons and the remaining atomic mass. It mentions the Hantaro Nagaoka atomic model, in which electrons are arranged in one or more rings, with a specific metaphoric structure of Saturn's stable rings. The plum pudding model of J. J. Thomson also has an orbiting electron ring. Jean Baptiste Perrin claimed in his Nobel lecture that he was the first to propose this model in his 1901 paper.

Rutherford's paper shows that the central charge of the atom may be "proportional" to its atomic mass in units of hydrogen mass (about 1/2 of that, in Rutherford's model). For gold, this mass number is 197 (then known for its extraordinary accuracy) and is therefore modeled by Rutherford to be possible 196. However, Rutherford does not attempt to make a direct connection of the central charge to the atomic number, since the "golden atomic number" (at that time is just the place number in the periodic table) is 79, and Rutherford has modeled the cost to about 100 units (he actually suggested 98 units of positive payload, to make half of 196). Thus, Rutherford does not formally suggest two numbers (where the periodic table, 79, and nuclear charge, 98 or 100) may be exactly the same.

A month after the Rutherford newspaper appeared, a proposal on the exact identity of the atomic number and nuclear charge was made by Antonius van den Broek, and then confirmed experimentally within two years, by Henry Moseley.

This is a key indicator-

• The atomic electron cloud does not affect the scattering of alpha particles.
• Most of the positive charges of atoms are concentrated in relatively small volumes at the center of the atom, known today as the nucleus. The magnitude of this charge is proportional to (up to the amount of charge which can be about half of) the atomic mass of the atom - the remaining mass is now known to be largely associated with neutrons. This concentrated central mass and charge are responsible for deflecting alpha and beta particles.
• Heavy atomic mass such as gold is largely concentrated in the central charge region, since the calculations show it is not deflected or driven by high-alpha particle speed, which has very high momentum compared to electrons, but not by paying attention to the overall weight of atoms.
• The atom itself is about 100,000 (10 ⁵ ) times the diameter of the nucleus. This can be attributed to putting a grain of sand in the middle of a soccer field.

Maps Rutherford model

Contribution to modern science

After Rutherford's discovery, scientists began to realize that atoms are essentially not single particles, but consist of much smaller subatomic particles. Subsequent studies determined the exact atomic structure that led to the Rutherford gold foil experiment. The scientists have finally discovered that the atom has a positively charged nucleus (with the right amount of atomic charge) at the center, with a radius of about 1.2 ÃÆ'â € "10 ^-15 meter ÃÆ'â € [Atomic Mass Number] < soup> ¹ / ₃ . Electrons are found to be smaller.

Later, scientists discovered the expected number of electrons (equal to the atomic number) in the atom using X-rays. When the X-rays pass through the atoms, some are scattered while the rest pass through the atoms. Since X rays lose their intensity primarily due to scattering of electrons, by noting the decreasing levels of X-ray intensity, the number of electrons contained in the atoms can be accurately estimated.

src: www.birdvilleschools.net

Symbolism

Also see the Bohr model, which applies as well as the section below.

The Rutherford model is suspended into the idea of ​​many electrons in the ring, as per Nagaoka. However, once Niels Bohr modified this view into a picture of only a few planet-like electrons for light atoms, the Rutherford-Bohr model captures the public's imagination. It has since continued to be used as a symbol for atoms and even for "atomic" energies (though this is more accurately considered nuclear energy). Examples of their use over the past century include but are not limited to:

• The US Atomic Energy Commission logo, which is partly responsible for its use in relation to nuclear fission technology in particular.
• The International Atomic Energy Agency's flag is a Rutherford atom, covered in olive branches.
• The small US league baseball logo Albuquerque Isotopes are a Rutherford atom, with electron orbits forming the letter A.
• The same symbol, the atomic circle, is chosen as a symbol for the American Atheist, and has been used as a symbol of atheism in general.
• The Unicode Miscellaneous Symbols codepoint U 269B (?) uses Rutherford atoms.
• On the map, it is usually used to denote nuclear power installation.

src: i.ytimg.com

References

src: saylordotorg.github.io

External links

• Rutherford model by Raymond College
• Rutherford Model by Kyushu University

Source of the article : Wikipedia