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Period: to
Atomic Timeline
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Isaac Newton
Isaac newton was born on January 4, 1643. He died on March 31, 1727 at the age of 84. The study of matter traditionally on scales involves more mass than an atom. This is the scale that Newton addresses and it is not called the atomic theory. When 2 atoms attach together we call it chemistry. The properties of atom such as the structure of a crystal are part of classical physics not the atomic theory even though it refers to atoms. -
Isaac Newton
Newton recommended that atoms were held together by forces. He said that small particles should be able to affect and communicate with one another across a distance. When small perticles communicate like this it is called an interatomic bond. Some interatomic bonds are: Covalent bonds, Ionic bonds, Hydrogen bonds. -
Isaac Newton
Newton made a large contribution to all of the physical sciences.He never understood mechanics so his progress was limited in physics, astronomy, chemistry etc. Newtons work was the basis of classical mechanics. His work is the basis of the atomic theory. John Dalton used Newtons work to help develop the atomic theory. -
John Dalton
John Dalton was born in 1766 in Cumberland, England, He died in 1843 at the age of 77. His theories were based on 3 propositions. Matter is composed of very small prticles that are indestructable. These particles are called atoms. Atoms combine in numercial proportions. Elements combine to make compounds. point where matter is not broken down into anything smaller. -
John Dalton
John Dalton propsed in the early 19th century that there was a point where matter is not broken down into anything smaller. Atoms are tiny particles. Dalton rationalized the many laws of chemical combination. He made a mistake thinking that the simplest compound of 2 elements must be binary. Atoms of elements have a 1:1 ratio. Dalton gave O an atomic weight. He led the ways to fields of experimentation. -
Michael Faraday
Faraday’s early experiments with electricity mostly focused on solids and liquids. Before 1830 Faraday and some other had started to study the effect of an electric current on a gas. For this experiment Faraday used a pair of metal plates sealed in a glass tube. The tube was full of gas and the metal plates were connected to a series of batteries. The gas was then slowly pumped out of the tube. Faraday realised that when the gas in the tube was small the gas would begin to glow. -
Michael Faraday
Michael Faraday was born on September 22, 1791. He died on August 25, 1867. He was 76. Faraday made a discovery that led to the idea that there was an electrical component in atoms. He put 2 opposite electrodes in a solution of water. The solution of water contained a dissolved compound. The dissolved compound was accumulated on 1 electrode. The other element was deposited on the opposite electrode. Faraday clearly saw that electrical forces were the reason for the joining of atoms in compounds. -
Michael Faraday
Faraday studied the effects of electricity on solutions. Main term “electrolysis”. He split molecules with electricity. Faraday developed laws of electrolysis. Faraday himself wasn't a part of atomism. However, his work was part of the basis of the atomic theory. Michael Faraday realised that when the gas in the tube was small enough it would begin to glow -
Jame Clerk Maxwell
His theory predicted that the electron would spiral into the nucleus in a very small fraction of a second in the case of an orbiting electron. -
James Clerk Maxwell
James Clerk Maxwell was born on June 13, 1831. He later died on November 5, 1879. He was 48yo. In his research on electricity ad magnetism Maxwell’s main research was to make the mathematical framework. This would underlie Faraday’s results in his experiments on the field theory. There are 4 mathematical equations Maxwell produced. They are ranked with Sir Isaac Newton’s law of motion and Albert Einstein’s theory of relativity. The electro-magnetic field theory was introduced by Maxwell. -
James Clerk Maxwell
He also introduced the connection between the waves in light and electromagnets. Maxwell did a demonstration that demonstrated the connection between 2 forces. He showed and proved that a electromagnetic wave was possible. His laws predict that a charged particle orbits around an oppositely charged particle. This should make it emit light at a frequency related to the radius of the specific orbiting particle. E.g. an electron orbiting about the nucleus. -
Dmitri Mendeleev
Dmitri Mendeleev was born on 8 February in, 1834. He died on the February 2, 1907 at the age of 73. -Mendeleev did not always depend on his own work. He was in an agreement with other scientists from around the world. He would receive data that the had collected and uses both his information and their information to arrange the elements according to their properties. Dmitri is known for being the creator of the periodic table of elements. -
Dmitri Mendeleev
Dmitri was a Russian chemist. He predicted the properties of 3 potential elements. He was the founder of the periodic law. -
Dmitri Mendeleev
Dmitri stated the periodic law and developed the periodic table. He felt that there was some kind of order to the elements. He spent 13 years of his life collecting information ad assembling the concept. Starting off with the idea of resolving some of the disorder in the field. He developed the period classification of the elements. Dmitri made his own version of the periodic table. In his version of the periodic table he left gaps in spots where he thought unknown elements would fit in. -
Wilhelm Roentgen
Ordinary light cannot penetrate materials unlike X-rays because they are a type of radiation. X-rays allow us to see the insides of the human body without having to cut it open. We use X-rays to locate bone fractures, cancerous tumours and tooth cavities. -
Wilhelm Roentgen
Wilhelm Roentgen was born on March 27, 1845. He died on February 10, 1923. He was 78 years old. In 1895. In 1895, Roentgen studied the phenomena that accompanied the passage of an electric current through a gas of really low pressure. Also in 1895, Roentgen experimented with cathode rays. He discovered different and new kinds of rays. He learned that if he directed these rays at a paper plater covered in barium platinocyanide the plate would turn fluorescent. -
Wilhelm Roentgen
Through other experiments he discovered that rays created images on photographic plates. These rays were know as Roentgen Rays but we know them as X-rays. They are part of the electromagnetic spectrum Other scientist such as: J. Plucker, J. W. Hittorf, C. F. Varley, E. Goldstein, Sir William Crookes, H. Hertz, and Ph. von Lenard, had already worked on this field. The work of these scientists the properties of cathode rays had become greatly known. -
Joseph John Thomson
Joseph John Thomson was born on the 18 December, 1856. He died on the 30 August, 1940. Thomson did cathode ray experiments. He said the emitted ray was formed by negative charges because they were connected by a positive pole. He knew that the atoms were elitrically neutral. Atoms should have the same quantity of negative and positive charges. Thomson named negative charges electrons. -
Joseph John Thomson
Thomson discovered electrons. He discovered electrons using a series of experiments. The experiments were designed to study the electrical discharge. He used high-vacuum cathode-ray tubes in his experiments. Thomson interrupted the deflection of rays using electrically charged magnets & plates. -
Joseph John Thomson
In 1904 he suggested the atom is sphere shaped because of the positive matter. Electrons are located by electrostatic forces. Thomson estimated the number of electrons in an atom by using measurements from light, and gamma rays. When he bcame older his student was Ernest Rutherford. J.J Thomson was a scientist who named negative charges electrons. -
Marie Curie
Marie Curie was on 7 November, 1867. She died on 4 July, 1934 at the age of 67. Henri Becquerel discovered radioactivity in 1896. This made Marie inspired in her researches. This led to the isolation of polonium. Marie developed methods for the separation of radium from radioactive residues. She did this in sufficient quantities to allow for its characterisation. She carefully studied of it’s therapeutic properties. Marie and Pierre studied radioactive materials especially pitchblende. -
Marie Curie
In 1898 the couple announced the existence of an unknown radioactive substance found in pitchblende. The substance was more radioactive then uranium. Over the years they processed lots of pitchblende. This was so they could concentrate the radioactive substances. Eventually they isolated the chloride salts When they did this they discovered 2 new chemical elements: Polonium and Radium. Marie Curie died of leukaemia from being exposed to radioactive materials for too long. -
Marie Curie
In 1898 Marie and Pierre isolated many substances by successive chemical reactions and crystallizations of products. They tested the ability to ionize air. The Curies then announced their discovery of polonium and radium salts. These weighed about 0.1 gram. It had been derived from tons of uranium ore.After Pierre died Marie produced a pure specimen of radium. -
Ernest Rutherford
This resulted on a paper about dividing atoms and molecules into ions. Rutherford went on to take a closer look at ion-producing radiations. Rutherford and Frederick Soddy introduced the theory of radioactivity. This claimed radioactive energy was released from within an atom. They also claimed that alpha beta particles were released at the same time, causing a chemical change across elements. Rutherford and Boltwood categorized radioactive elements into a “decay series”. -
Ernest Rutherford
Ernest Rutherford was born on the 30 August, 1871, He died on October 19, 1937 at the age of 66. J.J Thomson invited Rutherford to study X-rays with him. Wlhelm Conrad had already discovered X-rays months before Rutherford making it a hot topic among other research scientists. Rutherford and J.J studied the effects of X-rays together. They studied effects of X-rays on the conductivity of gases. -
Ernest Rutherford
Rutherford was credited for discovering the radioactive gas called radon. He achieved fame for his understanding of radioelements and he won a Nobel prize in 1908. He was nicknamed "Father of the Nuclear Age". -
Ernest Rutherford
Rutherford experimented further studying and involved firing alpha particles at foil.He discovered that nearly the total mass of an atom is made up of the nucleus. In doing this he created the nuclear model. This discovery marked the inception of nuclear physics. He prepared the way to the invention of the atom bomb. -
Albert Einstein
Albert Einstein was born on March 14, 1879. He died on April 18, 1955 at the age of 79. Einstein published an examination that pointed the way towards a test of the reality of atoms. The analysis was also about the validity of the laws of thermodynamics. The result of the test reinforces much of modern science. From our understanding of meteorology view to the atomic nature of matter and other complex systems. -
Albert Einstein
Einstein became famous for his theory of relativity. This laid the basis for the release of atomic energy. The new and modern atomic theory is also known as the quantum theory. Einstein contributed to the quantum theory by being against it. This caused Neil Bohr to create more models and explanations for it. So in the end Albert Einstein helped by criticism. -
Albert Einstein
Einstein’s theory expands the work of Max Plank. He analysed the effect of the light particles that are absorbed by a black surface. He speculated the presence of electrons that are made when beams of light are directed onto the surface of metal. This is called the photoelectric effect. When atoms are released by the photoelectric effect it causes a from of an electrical current. This theory gave a challenge to the idea that light travelled only in waves. -
James Chadwick
James Chadwick was born on October 20, 1891. He died on July 24, 1974 at the age of 83. Chadwick proved the existence of neutrons in 1932. This prepared the way towards the fission of Uranium 235 and the creation of the atomic bomb. In 1932 Chadwick was awarded the Hughes Medal of the Royal Society. He then won the Nobel Prize for Physics in 1935. Also in 1935 he was elected to the Lyon Jones Chair of Physics. James Chadwick proved that a neutrons are real. -
James Chadwick
It is also capable of splitting up the nuclei of even the strongest elements.Chadwick prepared towards the division of uranium 235 and towards creating the atomic bomb. -
James Chadwick
Chadwick made the discovery of the existence of neutrons in 1932. He did many experiments to do this. He figured out that elementary particles devoid of any electrical charge. In contrast with the helium nuclei which are charged, and therefore repelled by the considerable electrical forces present in the nuclei of heavy atoms. This is a new tool in atomic disintegration. The atomic disintegration’s new tool needs not to overcome any electrical barrier. -
Paul Dirac
Paul Dirac was born on 8 August 1902. He died on October 20 1984 at the age of 82. Dirac produced a mathematical equivalent by himself. This consisted of algebra calculating atomic properties. He wrote a series of papers on the subject and this lead up to his theory of the electron and his relativistic theory of holes. Dirac made basic contributions to the development of quantum mechanics, quantum field theories and quantum electrodynamics. -
Paul Dirac
In Dirac’s equation he allows 2 kinds of motion. Only 1 motion is familiar. The other motion is compatible to electrons with a weird motion. The faster they move the less energy they have andto make them rest you must put energy into them. This is called the positron which corresponds to an electron with a positive charge not a negative charge. The process on annihilation were an normal electron with positive energy drops in a hole. Fill up this hole and electromagnetic radiation is liberated. -
Paul Dirac
He is known for attempting to unify the theories of relativity and quantum mechanics. He made the Dirac equation in 1928 and he describes the behaviour of fermions to be like the electron. He predicted the existence of antimatter such as the positron. Paul Dirac and Erwin Schrödinger He won the Nobel prize in 1933. He discovered new productive forms of the atomic theory. Paul Dirac is nicknamed one of the greatest physicists of all time. The kinetic energy of a particle is always positive. -
Werner Heisenberg
Werner Heisenberg was born on Decemeber 5. He died at the age of 75 on Febraury 1, 1976. Niel Bohr said that an electron is a material particle of small mass. He said it revolves around the nucleus in circular orbits found at a fixed distance from the nucleus. Maxwell based some of his theories on Bohr’s research. Electrons go around the nucleus in a definite velocity or momentum. Heisenberg’s most memorable discoveries is the uncertainty principle. -
Werner Heisenberg
Heisenberg claimed that electrons don’t travel in neat orbits. He also claims all electrons that include photons will change momentum. His discovery assisted in clarifying the modern view of the atom. It did this because scientists can compare the small numbers of atoms. The do this by focusing on the electrons movement and how many electrons an atom contains. Around the outside of an atomic nucleus is and electron cloud. This is the name given to the electrons that are moving around. -
Glenn Seaborg
Glenn Seabord was born on 19 April, 1912. He later died on February 25, 1999 at the age of 87. Seaborg contributed to the study and discovery of more than 100 isotopes of many different elements. John Livingood, Fred Fairbrother and Seaborg discovered (Fe-59) an isotope of iron. Seaborg was part of the team that achieved success in isolating element 94 (plutonium). In 1941 Seaborg isolated Uranium-223. He then demonstrated that thorium had nuclear fuel potential. -
Glenn Seaborg
org added 8 elements to periodic table. He discovered 8 elements named:-Americium-Curium-Berkelium-Californium-Einsteinium-Fermium-Mendelevium-Nobelium-Seaborgium -
Glenn Seaborg
In 1951 Seaborg won the Nobel prize for discovering new trasuranium elements. Seaborg was also a leading force of the Manhattan Project where his group of scientists helped create the worlds first controlled nuclear chain reaction. He did this by converting uranium-238 into plutonium. The most important change in the periodic table is the formation of the actinide series. Seaborg formed this actinide concept between 1944 and 1958.
