Lowell.Hutchinson.Spring2010.AtomicTimeline

__Democritus__ Democritus was born in 460 BCE in Thrace. He was a major influence to almost every scientist ever. His atomic theory stated that all things were made up of atoms that are indivisible, indestructible, and will always be in motion. Also he said that between the atoms were empty space. He is considered to be the father of modern science, during his life time he was not as well known as another philosopher, Plato. Democritus was an extremely intelligent individual and basically, discovered what the atom was without any scientific technology to use at all. With the help of his teacher and mentor, Leucippus, Democritus came up with the well known atomic theory. The fact that Democritus came up with this idea of "atoms" (invisible parts) is truly remarkable. http://www.thebigview.com/greeks/democritus.html http://web.mit.edu/philos/www/mm/democritus.jpg

Leucippus was a Greek philosopher who was born in Abdera, Greece in 460 BCE. Leucippus was a mentor type figure for Democritus and a lot of Democritus published works on the atom and the atomic theory were due to reasearch with Leucippus. When it comes down to it, Leucippus and Democritus made their atomic theory by simply ignoring was known as pure fact in their lifetimes. Everyone in ancient times believed that "everything is one" and that change and motion is an illusion However, it was up to Leucippus (along with the help of Democritus) to make sense out of the everyday world around them. Therefore, these two in fact did so through their atomic theory. http://www.mlahanas.de/Greeks/images/Leucippus1.jpg


 * __Aristotle__**
 * (384-322 BCE)**

Aristotle was a Greek philosopher who was born in Stagira in Northern Greece in 384 BCE. He was trained under Plato of Pluto and was also the teacher of Alexander the Great. He wrote and studied about numerous different topics including; poetry, government and politics, logic, ethics, and physics. He was an extremely intelligent and gifted individual. Aristotle is even thought to be a key figure in the development in western philosophy. It truly was remarkable what Aristotle was able to do in his life with the lack of sources he had available. Aristotle lived in a time where there was little known about our world. However, Aristotle managed to discover that our world consisted of four majors parts; Fire, Water, Earth, and Air.

Aristotle discovered natures four major components; Fire, Water, Earth, and Air. By doing so, he put up the first stepping stone to the discovery of the atom in the extremely distant future. Aristotle was literally the first known person in the world to organize organisms in way that made sense. However, Aristotle did have another element called Aether. Aether was said by Aristotle who was an extremely religious individual to be the stars and planets, which are also the Greek Gods. However, when it comes down to it, if it wasn't for Aristotle's discovery, many of the well known scientists concerning the atom and its overall understanding couldn't have been able to do so, nor discover the amazing facts and parts about the atom. = http://galileoandeinstein.physics.virginia.edu/lectures/aristot2.html =

http://dopodomani.files.wordpress.com/2009/10/aristotle3.jpg

Joseph Black 1728-1799 Black was born April 16, 1728. He was a physician, physicist, and chemist from Scotland. He is known for discovering latent heat, carbon dioxide, and specific heat. Definition of latent heat: “The quantity of heat absorbed or released by a substance undergoing a change of state, such as ice changing to water or water to steam, at constant temperature and pressure. Also called //heat of transformation//.” Definition of specific heat: “The ratio of the amount of heat required to raise the temperature of a unit mass of a substance by one unit of temperature to the amount of heat required to raise the temperature of a similar mass of a reference material, usually water, by the same amount.” He was the mentor for James Watt, and was a founder of thermo chemistry. The chemistry buildings at both the University of Edinburgh and the University of Glasgow are named after him. Joseph Black was the first person to isolate Carbon dioxide as a pure element, showing that air was made up of many different elements. This helped support the atomic theory and dismiss the theory that air was a pure element. Air was known to be a pure element since Aristotle. [] [] [|http://www.chem.gla.ac.uk/~alanc/dept/black.htm] http://www.general-anaesthesia.com/images/joseph-black.jpg

Charles-Augustin de Coulomb 1736 –1806. Coulomb came from a wealthy French family and attended college at the prestigious College des Quatre-Nations. There he studied as a mathematician under Pierre Charles Monnier. He is most widely known for the SI unit for charge named after him, coulomb, and for developing Coulomb's law. Coulomb's advances for the atom theory, was his research on the electrostatic forces of attraction and repulsion. Though he did not know it, these discoveries would later be used to come up with the proton and electron theory. Coulomb’s Law: The fundamental law of electrostatics stating that the force between two charged particles is directly proportional to the product of their charges and inversely proportional to the square of the distance between them. [] [] http://www.colorado.edu/physics/phys3310/phys3310_sp09/images/coulomb3.gif

Antoine Lavoisier abolished the phlogiston(A hypothetical substance formerly thought to be a volatile constituent of all combustible substances, released as flame in combustion.) theory, came up with the first law of conservation of mass, and came up with an extensive list of elements. He also recognized and named oxygen and hydrogen. He reorganized chemical nomenclature. This man is under appreciated for his role in making the periodic table what it is today. [] [] http://www.homeoint.org/morrell/articles/photo/lavoisier.jpg

John Dalton (4) 1766-1844 John Dalton was born on September 6, 1766 in Cumberland England. Dalton started out his theories with one that stated colorblindness was caused by a discoloration of the liquid medium of the eyeball. This was proven to be false, but got his name out there. Dalton is famous for his five main points of the atomic theory. These were thought to be true until proven otherwise, but put scientists on the right track to figuring out how it really works. His 5 main points were: 1. The atoms of a given element are different from those of any other element; the atoms of different elements can be distinguished from one another by their respective relative atomic weights. 2. All atoms of a given element are identical. 3. Atoms of one element can combine with atoms of other elements to form chemical compounds; a given compound always has the same relative numbers of types of atoms 4. Atoms cannot be created, divided into smaller particles, nor destroyed in the chemical process; a chemical reaction simply changes the way atoms are grouped together. 5. Elements are made of tiny particles called atoms. Daltons 5 rules on atomic theory were to be well known up to today. He is considered to be one of the founding fathers of modern atomic laws.

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__Johann Josef Loschmidt__

Johann Josef Loschmidt was born on March 15th 1821 and died in July 8th 1985. He provided groundbreaking discoveries in chemistry, physics and crystal forms. He had two early mentors, the first was a Bohemian priest, Adalbert Czech, who persuaded Loschmidt's parents to send young Josef to high school in the Piarist monastery in Schlackenwerth and, in 1837, to advanced high-school classes in Prague. He became a professor in 1868 at the University of Vienna as a professor in physical chemistry. His second mentor was philosophy professor Franz S. Exner. Exner was known for his innovative school reforms, which included promoting mathematics and science as important subjects. In 1865, Loschmidt was the first to estimate the size of the molecules that make up the air, his result was only twice the true size, a remarkable feat given the approximations he had to make. His method allowed the size of any gas molecules to be related to measurable phenomena, and hence to determine how many molecules are present in a given volume of gas. [] [|http://www.armstrongwynne.org/images/loschmidt.jpg]

__Dmitri Mendeleev__

Dmitri Mendeleev was born on febuary 8th 1834 and died on February 2nd 1907. He was born to Ivan Pavlovich Mendeleev and Maria Dmitrievna Mendeleeva. Mendeleev is thought to be the youngest of 14 siblings, but the exact number differs among sources. At the age of 13, after the passing of his father and the destruction of his mother's factory by fire, Mendeleev attended the Gymnasium in Tobolsk. After becoming a teacher, he attempted to classify the elements according to their chemical properties; he noticed patterns that led him to postulate his Periodic Table. Mendeleev was unaware of the other work on periodic tables going on in the 1860s. He made the following table, and by adding additional elements following this pattern, developed his extended version of the periodic table. In 1906 the Nobel Committee for Chemistry recommended to the Swedish Academy to award the Nobel Prize in Chemistry to Mendeleev for his discovery of the periodic system. [] http://www.bluffton.edu/~bergerd/nsc_111/images/Mendeleev.gif

__George Johnstone Stoney__ = George Johnstone Stoney was born on February 15th 1826 and died on July 5th 1911. He attended Trinity College, Dublin Ireland, graduating with a B.A. in 1848 and an M.A. in 1852. Later in 1852 Stoney became a professor at Queens College teaching Natural Philosophy. But was most famous for introducing the term “electron” as a fundamental unit quantity of electricity. The word first appeared in 1891 in one of his seventy-five papers and journals he wrote throughout his lifetime. = = http://www.irishmidlandsancestry.com/content/offaly/people/stoney_johnstone.htm = http://understandingscience.ucc.ie/img/sc_George_Johnstone_Stoney.jpg

Antoine Henri Becquerel (5) 1852-1908

Antoine Henri Becquerel was born December 15, 1852 in Paris, France. He was chief engineer in the department of bridges and highways. In 1896 while investigating phosphorescence in uranium salts he accidentally discovered radioactivity. He made an experiment intended for use in bright light, but after coming into the lab in the morning to start the experiment he found that the plates he was using was already exposed to the emission of nuclear radiation even though he never exposed them to light. “One wraps a Lumière photographic plate with a bromide emulsion in two sheets of very thick black paper, such that the plate does not become clouded upon being exposed to the sun for a day. One places on the sheet of paper, on the outside, a slab of the phosphorescent substance, and one exposes the whole to the sun for several hours. When one then develops the photographic plate, one recognizes that the silhouette of the phosphorescent substance appears in black on the negative. If one places between the phosphorescent substance and the paper a piece of money or a metal screen pierced with a cut-out design, one sees the image of these objects appear on the negative. … One must conclude from these experiments that the phosphorescent substance in question emits rays which pass through the opaque paper and reduces silver salts.” This is what he stated to the French academy of sciences describing his methods. He won the Nobel Peace Prize for his findings and shared his fame with Marie Curie for the finding of the radiation. [] http://nobelprize.org/nobel_prizes/physics/laureates/1903/becquerel.jpg

Wilhelm Conrad Röntgen (6) 1845-1923

Wilhelm Conrad Röntgen was born on March 27, 1845 in what is now Rhenish Prussia. He was expelled from his private high school because he violated the honor code. However Rontgen graduated the University of Zurich with a Ph.D in mechanical engineering. Before World War One, the great Germany physicist had plans to immigrate to the United States but these plans were crushed by the start of the war. In 1895, Rontgen produced the first X ray by expanding on the research completed with vacuum tubes when an electrical current is passed through them. The first X ray was of his wife' left hand and shows a large ring on her ring finger. William Rontgen died on February 10, 1923 at the age of 77 in Munich, Germany of intestinal cancer. William Rontgen's most crucial discovery was that of electromagnetic radiation in the form of a wavelength range. in modern terms, he discovered X rays which are used in numerous applications throughout society. On November 8, 1895, Rontgen produced the first x ray almost on complete accident. Well performing research with cathode rays and vacuum tubes, Rontgen produced an electrostatic charge around a vacuum tube causing a completely different ray other than light to be formed. After a couple of weeks of constant observation, Rontgen took and developed his first picture utilizing x rays. The picture was of his wife's left hand.

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__J.J Thomson__ was born on December 18, 1856 in Manchester England. He went to Owens College in Manchester and then Trinity in 1880. He then later became a professor at Cambridge where he documented most of his experiments. In 1897 he discovered that cathode rays had to of had some sort of negatively charged particles within them. Thomson was trying to investigate whether or not cathode rays could be deflected by an electric field. His first experiment failed in his first experiment with cathode rays and magnetism then moved on the disc. He constructed a cathode ray tube and created an almost perfect vacuum inside the design. Then he coated one end with phosphorescent paint. From this he discovered the cathode rays did bend under the influence of an electric field, in a direction indicating a negative charge. JJ received the Nobel Peace Prize in 1937 for proving wavelike properties in electrons in this experiment. He ended up dying on august 30, 1940. = http://nobelprize.org/nobel_prizes/physics/laureates/1906/thomson-bio.html =

http://upload.wikimedia.org/wikipedia/commons/5/5e/JJ_Thomson.jpg

Marie Curie (8) 1867-1934

Marie Curie was born on November 7, 1867 in the Russian Empire. At the age of 24 she travelled to Paris. She studied sciences and subsequently founded the Curie Institutes of science. Her husband Pierre Curie served as a great partner to her scientific studies in radioactivity. She was the first female professor at the University of Paris. Her main discoveries were the establishment of the theory of radioactivity, the discovery of two new elements, and the applications of radioactive isotopes in the treatment of cancers. She passed away in 1934 due to cancer caused by her direct contact with radioactive materials because throughout her entire career she did not employ proper safety techniques. The two main discoveries of Marie Curie and her husband Pierre were the establishment of the radioactive theory and the discovery of two new radioactive elements. The scientific couple discovered Polonium and Radium in 1898. Marie concentrated the elements by sifting through tons of pitchblende and isolating the elements. In 1903 Marie was awarded the Nobel Prize for her great contribution to the research of the "radiation phenomena." she was the first female to win the Nobel Prize. http://www.aip.org/history/curie/polgirl1.htm http://www.erau.edu/er/newsmedia/newsreleases/2007/images/curie.jpg

__Robert Millikan 1868-1953__ Robert Millikan was born on the 22nd of March, 1868, in Morrison, Illinois. He attended Maquoketa High School in Iowa. For college he went to Oberlin College and then got his Ph.D. in Physics from Columbia University in 1895. From there, he went from university to university teaching all around Europe, gaining knowledge of different experiments from different parts of Europe. His most famous was when he discovered the charge and mass of an electron in his oil drop experiment. Robert Millikan discovered the charge and mass of an electron. First, Millikan had oil drops falling through a chamber and wait until they reached terminal velocity. Next he filled the same chamber with X-rays, to get rid of the electrons. Then when the oil droplets his the x-rays, they became negatively charged and he created a magnetic field within the chamber by attaching a battery. By adjusting the voltage till the force of electric field balanced with the force of gravity, the oil droplets would suspend in air start to rise. With this knowledge he used a few formulas and found the charge of an electron and Robert won the Nobel Peace Prize for this in 1923. He ended up dying December 19th 1953. http://nobelprize.org/nobel_prizes/physics/laureates/1923/millikan-bio.html http://www-news.uchicago.edu/releases/06/images/061128.millikan.jpg

__Ernest Rutherford__ (1871–1937) Ernest Rutherford was a physicist who became known as the major player in nuclear physics and was even known as “the father of physics,” and lived in New Zealand. He was originally from Hornchurch, Essex England. He studied at Havelock School and then Nelson College and gained a scholarship to study at Canterbury College. His discoveries started in 1911 when he discovered an atoms positive charge is concentrated in a small nucleus in the center of an atom. He also came up with the planetary model for the atom, through his discovery and interpretation of Rutherford scattering in his gold foil experiment. His gold foil experiment consisted of him shooting atoms through a very thin sheet of gold foil. Most of the atoms when right through the gold sheet, some bounced at an angle and some hit the sheet and came back in the same direction. This is how he concluded the theory of a nucleouse. He was also the first person to split the atom in 1917. http://www2.slac.stanford.edu/vvc/nobel/rutherford.html http://www.wpclipart.com/famous/science/science_2/Ernest_Rutherford.png

__Niels Bohr__ 1885-1962

Niel Bohr was born on October 7, 1885 and died on November 18, 1962. He was born to Christian Bohr and Ellen Adler Bohr. Bohr Studied at Copenhagen University in 1903 in which majored in philosophy and mathematics. Later in 1916 Bohr became a professor at his university. He received the Nobel peace prize in physics in 1922 for making contributions to the understanding of the atomic structure and quantum mechanics. Bohr was involved in the “Manhattan Project” which was a top secret state or work in which the development of the atom bomb was taking place. His role in the project was the knowledgeable consultant. His belief though was the information gained should be shared with the Russians and the international scientific community. Both Roosevelt and Churchill disagreed with this idea. Later after the war Bohr went back to Copenhagen and pushed the idea of using nuclear energy as a peaceful manner rather than a use of war. http://nobelprize.org/nobel_prizes/physics/laureates/1922/bohr-bio.html http://www.atlco.com/blog/wp-content/uploads/2009/04/niels_bohr.jpg

__Erwin Schrodinger__ 1887-19--

Erwin Schrodinger was born on August 12, 1887 to Rudolf Schrodinger and Georgine Emilia Brenda, and passed away on January 4th 1961. In 1898 he attended Akademisches Gymnasium. And through 1906 till 1910 he studed under Franz Serafin Exner and Friedrich Hasonohrl. In 1914 Erwin Schrödinger became Habilitations and between 1914 and 1918 he participated in war work as a commissioned officer in the Austrian fortress artillery In 1939 after Anscheluss, he had problems with the government because in 1933 he had fled from Germany due the the Nazis in power. Also in 1933 he won the Nobel Peace Prize for his studies and contributions in quantum mechanics. http://nobelprize.org/nobel_prizes/physics/laureates/1933/schrodinger-bio.html http://scienceblogs.com/builtonfacts/2008/09/28/sch

__James Chadwick 1891-1974__

Chadwick was born in Bollington, Cheshire on October 20, 1891 to John Joseph Chadwick and Anne Mary Knowles and died on July 24, 1974. He went to Bollington Cross C of E Primary School, attended the Central Grammar School for Boys in Manchester, and then studied at the Universities of Manchester and Cambridge. In 1932, Chadwick discovered a previously unknown particle in the atomic nucleus. This particle became known as the neutron because of its lack of an electric charge. For this discovery he was awarded the Hughes Medal of the Royal Society in 1932 and the Nobel Prize for Physics in 1935. In 1945 he went to the Unites states to help with the manhattan Project to help develop the atom bomb. http://www.aps.org/publications/apsnews/200705/images/chadwick_web.jpg

Werner Heisenberg 1901-1976

Werner Heisenberg was born on December 5, 1901 in Wurzburg, Germany. He studied physics and mathematics at the University of Munich. In his earlier years as a scientist Heisenberg worked with Neils Bohr at the University of Copenhagen. Most of his work was done establishing the basics of quantum mechanics by contributing the uncertainty principle of quantum theory. As a German scientist, Heisenberg was a major contributor to the Uranium Club, the Nazi's attempt to build an atomic bomb. In 1927, Heisenberg published a paper on his uncertainty principle of quantum theory. It was too complicated for most scientists even in his field to understand. http://www.ph.surrey.ac.uk/astrophysics/files/Werner.jpg


 * __ Small, spherical, solid, indivisible model __**

Stated that all things were made up of atoms that are indivisible, indestructible, and will always be in motion. between the atoms were empty space. http://reich-chemistry.wikispaces.com/file/view/SOLIDsdsdahj231.gif/97930493/SOLIDsdsdahj231.gif

__Plum Pudding model__

In JJ Thomson’s "Plum Pudding Model," each atom is a sphere filled with a positively charged “pudding” like substance. Located randomly in this fluid are electrons known as the "plums." Thomson suggested that the positive pudding held the negative charges, the electrons, in the atom because of electrical forces. http://home.iitk.ac.in/~sreerup/bso203/PlumPudding.gif

__Rutherford-Bohr model__

The Rutherford-Bohr model shows the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus. http://www.mrhood.co.uk/pub/wp-content/uploads/2006/12/rutherford-model1.png


 * __ Planetary Atomic Model __**

The Planetary model for the atom had a number of features that are still believed to be true in today's view of the atom. A high central charge concentrated into a very small volume compared to the rest of the atom. It also contained the bulk of the atomic mass, and a number of tiny electrons orbiting around the nucleus like planets. http://reich-chemistry.wikispaces.com/file/view/planetary_model.png/104111219/planetary_model.png

This theory states that an atrom consists of dense nucleus made of neutrons and protons. The nucleus is surrounded by electrons that exist in diferent clouds at various energy levels. http://www.csmate.colostate.edu/cltw/cohortpages/viney_off/atom.jpg
 * Electron cloud model **