Ernest Rutherford was a British physicist born in New Zealand who was among the leading scientists of the twentieth century. He made a primary contribution to the sciences of Physics and Chemistry through his study of radioactivity and the structure of the atom.
Because of his pioneering work in the field, Rutherford is known as the Father of Nuclear Physics. Among other things, he invented a radio receiver, discovered that atoms were not indestructible, discovered alpha and beta radioactivity, interpreted the famous gold foil experiments to form the Rutherford model of the atom, discovered the atomic nucleus and the proton, and performed the first induced nuclear reaction.
Rutherford was also considered the greatest experimentalist since Michael Faraday and won the Nobel Prize in Chemistry in 1908. Learn more about his scientific achievements through his 10 major contributions.
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He invented an early radio wave detector
The German physicist Heinrich Hertz demonstrated the existence of electromagnetic waves in the late 1880s. Rutherford decided to measure their effect on magnetized steel needles. His experiments led him to invent a detector for what we now know as radio waves.
This radio receiver became part of the communications revolution known as wireless telegraphy. Rutherford improved his device and for a brief period kept the world record for the distance over which electromagnetic waves could be detected.
Although Rutherford was surpassed by Guglielmo Marconi, who became the most prominent figure in the field of wireless telegraphy, his receiver is still considered an important contribution.
Guglielmo MarconiGuglielmo Marconi
Ernest Rutherford discovered alpha and beta radioactivity
In 1898, Ernest Rutherford began studying the radiation emitted by uranium. His experiments led him to conclude that radioactivity must have at least two components; and named them alpha and beta rays after the first two letters of the Greek alphabet.He discovered that alpha particles are positively charged and that they are helium ions that carry a +2 charge. He also discovered that beta rays have more penetration power than alpha rays. Rutherford also coined the name of gamma rays, which were discovered by French physicist Paul Ulrich Villard in 1900.
Diagram of the radioactive substance that produces the alpha, beta and gamma rays Rutherford studied the radiations emitted by radioactive substances and coined the terms alpha, beta and gamma
He discovered the principle of half-life and applied it to radiometric dating.
During his study of radioactivity, Rutherford found that it invariably took the same amount of time for a sample of radioactive material, radio, of any size, to break down in half. of its initial size.
He coined the term “half-life period” for this principle, which he had discovered. Rutherford applied this half-life principle of a radioactive element to study “how old things are” by measuring the period of decomposition of the lead-206 radius, thus initiating the science of radiometric dating for age determination.
Radioactive decay chart Graph explaining radioactive decay with half-lives
Rutherford discovered that atoms were not indestructible
In 1900, English chemist Frederick Soddy joined Rutherford in his research on radioactivity. Together they demonstrated that it involved the spontaneous disintegration of atoms into other types of atoms.
They invented the “Atomic Disintegration Theory” to explain all their experiments. The atoms of the radioactive elements that break, it was a historical discovery since until then it was believed that the atoms were the indestructible base of all matter.
It was for his research on the disintegration of elements and the chemistry of radioactive elements that Rutherford received the Nobel Prize in Chemistry in 1908.
Radioactive decay diagram Radioactive decay diagram
He formulated the Rutherford model of the atom in 1911
Together with researchers Hans Geiger and Ernest Marsden, Rutherford conducted one of the most important scientific experiments, known as the Geiger-Marsden experiment or the Rutherford gold leaf experiment.
Under the direction of Rutherford, Geiger and Marsden conducted a series of experiments between 1908 and 1913 in which they aimed a beam of alpha particles at a thin sheet of metal and measured the dispersion pattern using a fluorescent screen.
They discovered that while most of the particles flew straight they threw the coil, some bounced in all directions, even back to the source.
This behavior was impossible to justify by the prevailing model of the atom at that time, the JJ Thomson plum pudding model. Rutherford thus interpreted the data to formulate the Rutherford model of the atom in 1911.
Ernest Marsden and Hans Geiger Ernest Marsden (left) and Hans Geiger (right)
He analyzed the gold foil experiments to discover Rutherford’s dispersion
The Geiger-Marsden experiments led Rutherford to discover and interpret the elastic dispersion of charged particles that interact according to the Coulomb inverse grid law, now known as the Rutherford dispersion.
Since then, Rutherford dispersion has been used frequently to study the structure of the atom. Rutherford later also analyzed the inelastic dispersion, but it is not known as the Rutherford dispersion, although he was the first to observe it.
In the inelastic dispersion, the kinetic energy of an incident particle is not conserved, unlike the elastic dispersion. Rutherford’s technique also led to backscatter spectrometry of Rutherford (RBS), an analytical technique used in materials science.
Diagram of the Geiger-Marsden experiment Diagrammatic representation of the Rutherford Gold Foil Experiment
Ernest Rutherford discovered the atomic nucleus
Through the gold foil experiments, Rutherford discovered that each atom contains a nucleus where its positive charge is concentrated, and most of its mass.
His model of the atom thus contained the new characteristic of a relatively high central charge concentrated in a small volume of the atom and responsible for most of its mass.
In the model, the nucleus was orbited by low-mass electrons. Rutherford’s atomic model was replaced by Bohr’s atomic model in 1913, which, most prominently, applied quantum theory.
Rutherford’s discovery of the atomic nucleus was extremely relevant and is considered his greatest contribution to science, although he received the Nobel Prize for his study of radioactivity.
Rutherford model of the atom diagram Basic scheme of the Rutherford model of the atom
He discovered the proton in 1917
In 1917, Ernest Rutherford became the first person to deliberately transform one element into another. He turned nitrogen atoms into oxygen atoms by bombarding nitrogen with alpha particles.
This was the first observation of an induced nuclear reaction and proton discovery is also considered. The reaction was initially written as 14N + α → 17O + 1H. The result showed Rutherford that hydrogen nuclei were part of nitrogen nuclei and began to suspect that hydrogen nuclei could actually be a fundamental particle.
In 1920, he proposed the hydrogen nucleus as a new particle and coined the term proton for it. The nuclear reaction could now be written as 14N + α → 17O + proton.
Diagrammatic representation of the induced nuclear reaction Diagrammatic representation of the induced nuclear reaction performed by Rutherford
Theorized the existence of the neutron
Rutherford performed calculations of the stability of atomic nuclei. In 1921, while working with Niels Bohr, he theorized that there should be a neutral particle in the nucleus to compensate for the repellent effect of positive proton charges causing an attractive nuclear force.
In the absence of such a particle, the repulsion would cause the nucleus to fly apart. Rutherford thus theorized the existence of the neutron and even coined the term by which it is known. His prediction was demonstrated by the discovery of the neutron in 1932 by the English physicist James Chadwick, who had studied and worked with Rutherford.
He is known as the Father of Nuclear Physics
Ernest Rutherford is known as the Father of Nuclear Physics for his work in the field, including the conduct of the first induced nuclear reaction, the establishment of the nuclear structure of the atom, and the proof of the nature of the radioactive decay of a process nuclear.
His work was of paramount importance for research and development in this field. Rutherford also provided inspiration and guidance to future scientists and an unusually large number of his students won the Nobel Prizes. Rutherford was also considered the greatest experimentalist since Michael Faraday.