What particles did Rutherford discover? Experience and scheme of Rutherford's experience
Ernest Rutherford is a brilliant scientist who committedseveral truly great discoveries in chemistry and physics. What progress has physics led to in a new way of development? What particles did Rutherford discover? Details of the biography and scientific activities of the researcher find out in the article.
The beginning of the life path
Biography of Rutherford begins with a smallthe town of Spring Grove in New Zealand. There in 1871 a future physicist and scientist was born into a family of immigrants. His father, a Scotsman by birth, was a woodworking master and had his own enterprise. From it, Rutherford acquired useful design skills for subsequent work.
The first successes are already in school, where forexcellent study he received a scholarship for college. First, Ernest Rutherford studies at Nelson's College, then goes to Canterbury. Having a wonderful memory and brilliant knowledge, he is noticeably different from other students.
Rutherford receives an award in mathematics, writesthe first scientific work on physics "Magnetization of iron in high-frequency discharges." In connection with the work, he invents one of his first instruments for recognizing magnetic waves.
In 1895, physicist Rutherford argues with a chemistMaklorenom for the possession of the scholarship of the name of the World Exhibition. By coincidence, the rival refuses the award, and Rutherford is given a lucky chance to conquer the scientific world. He goes to England to the Cavendish Laboratory and becomes a doctor of science under the direction of Joseph Thomson.
Scientific works and achievements
Arriving in England, the student barely has enoughscholarships. He begins to work as a tutor. The scientific leader of Rutherford immediately noted his enormous potential, and was not mistaken. Thomson invited the young physicist to study the ionization of the gas by X-rays. Together, scientists discovered that the phenomenon of current saturation arises.
After successful work with Thomson, he deepensin the study of the rays of Becquerel, which later Maria Sklodowska-Curie will call radioactive. At this time, he makes his first important discovery, revealing the existence of particles unknown before this, studying the properties of uranium and thorium.
Later he became a university professor inMontreal. Together with Frederick Soddy, the scientist puts forward the idea of transforming elements in the process of decay. At the same time, Rutherford wrote scientific works "Radioactivity" and "Radioactive Transformations", which bring him fame. He becomes a member of the Royal Society, is awarded a noble title.
For studies of the decay of radioactive elements inIn 1908 Ernest Rutherford was awarded the Nobel Prize. The scientist discovered the emanation of thorium, the artificial transmutation of elements upon irradiation of nitrogen nuclei, and wrote three volumes of works. One of his most important achievements is the creation of a model of the atomic nucleus.
What particles did Rutherford discover?
In the study of radioactive radiation, Rutherford wasnot the first. Before him, this area was actively mastered by the physicist Becquerel and the Curie couple. The phenomenon of radioactivity was discovered only recently, and energy was considered an external source. By carefully studying uranium salts and their properties, Rutherford observed that the rays discovered by Becquerel are inhomogeneous.
The experiment of Rutherford with foil showed thatThe radioactive ray is divided into several streams of particles. One stream of aluminum foil is able to absorb, the other can pass through it. Each of them is a set of small elements called by the scientist alpha and beta particles or rays. Two years later, the Frenchman Villar opened the third type of rays, which, as Rutherford called, was called gamma rays.
What particles Rutherford discovered hada huge influence on the development of nuclear physics. A breakthrough was made and it was proved that the energy comes from the uranium atoms themselves. Alpha particles were defined as positively charged helium atoms, beta particles were electrons. Gamma particles discovered later are electromagnetic radiation.
Radioactive decay
Opening of Rutherford gave impetus not onlyphysical science, but also to himself. He continues to study radioactivity at the University of Montreal in Canada. Together with the chemist Soddy, they conduct a series of experiments, by which they note that the atom changes during the emission of its particles.
Like the medieval alchemists, scientistsconvert uranium into lead, making another scientific breakthrough. Thus, radioactive decay was discovered. The law according to which the decay occurs, Rutherford and Soddy described in the works "Radioactive transformation" and "Comparative study of the radioactivity of radium and thorium."
Researchers define the dependencethe intensity of decay from the number of radioactive atoms in the sample, and also from the past tense. It was noted that with the passage of time the decay activity decreases in a geometric progression. For each substance it takes time. On the basis of the rate of decay, Rutherford succeeded in formulating the principle of half-decay.
The planetary model of an atom
At the beginning of the XX century, manyexperiments on the nature of atoms and radioactivity. Rutherford and Villar open alpha, beta and gamma rays, and Joseph Thomson in turn opens the electron. He measures the charge-to-mass ratio of an electron and verifies that the particle is part of the atom.
On the basis of his discovery, Thomson creates a modelatom. The scientist believes that the latter has a spherical shape, on the whole surface of which positively charged particles are distributed. Inside the ball there are negatively charged electrons.
A few years later, Rutherford disproves the theoryhis teacher. He claims that the atom has a nucleus that is positively charged. And around him, like planets around the sun, electrons spin under the influence of Coulomb forces.
Scheme of Rutherford's experiment
Rutherford was an outstanding experimenter. Therefore, doubting the model of Thomson, he decided to refute it by experience. Thomson's atom should look like a spherical cloud of electrons. Then the alpha particles must pass freely through the foil.
For the experiment, Rutherford designed the deviceFrom a lead box with a small hole in which the radioactive material was. The box absorbed alpha particles in all directions, except where the hole was. This created a directional flow of particles. Ahead were several lead screens with slots to weed out particles that deviate from the given course.
A clearly focused alpha ray passed throughall obstacles, was directed to a very thin sheet of gold foil. Behind her was a fluorescent screen. Each contact of particles with it was registered in the form of a flash. So it was possible to judge the deviation of the particles after passing through the foil.
Surprisingly Rutherford himself, many particlesdeviated at great angles, some even at 180 degrees. This allowed the scientist to assume that the bulk of the atom is a dense substance inside it, which is later called the nucleus.
Scheme of Rutherford's experience:
Criticism of the model
The nuclear model of Rutherford was first subjected tocriticism, because it was contrary to the laws of classical electrodynamics. Rotating, electrons must lose energy and radiate electromagnetic waves, but this does not happen, which means they are at rest. In this case, the electrons should fall on the core, rather than spinning around it.
To deal with this phenomenon fell Nils Bohr. He establishes that each electron has its own orbit. While the electron is on it, it does not emit energy, but has acceleration. The scientist introduces the concept of quanta - portions of energy, which is released when electrons move to other orbits.
Thus, Niels Bohr became one of thethe founders of a new branch of science - quantum physics. The correctness of the Rutherford model has been proved. As a result, the concept of matter and its movement have completely changed. And the model is sometimes called the Bohr-Rutherford atom.
Interesting facts about the scientist
Nobel Prize Ernest Rutherford received earlier than committed the most important achievement of his life - discovered the atomic nucleus and installed a planetary model of the atom.
The remarkable discovery of Rutherford led to the emergence of a new industry that is studying the structure of the atomic nucleus. It was called nuclear or nuclear physics.
The physicist possessed not only research, but alsoteaching talent. Twelve of his students were Nobel laureates in the field of physics and chemistry. Among them are Frederic Soddy, Henry Moseley, Otto Gan and other famous personalities.
A scientist is often credited with the discovery of nitrogen thatis erroneous. After all, this is another famous Rutherford. The gas was discovered by the botanist and chemist Daniel Rutherford, who lived a century before an outstanding physicist.
Conclusion
British scientist Ernest Rutherford became famousamong colleagues craving for experiments. Throughout his life, the scientist has conducted many experiments, through which he managed to open alpha and beta particles, formulate the law of decay and half-life, develop a planetary model of the atom. Before it was believed that energy is an external source. But after the scientific world learned what particles Rutherford had discovered, physicists changed their minds. The achievements of the scientist helped to make huge strides in the development of physics and chemistry, and also contributed to the emergence of an industry such as nuclear physics.
