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460 BCE
Democritus
Democritus was a Greek philosopher who lived in the 5th century. Democritus knew there was a point were a substance was so small that it was indivisible and couldn’t shattered. This substance is called Atomos. Democritus also created the idea of atoms with is an atom in the smallest unit of matter which still retains the identity and properties of that matter. -
384 BCE
Aristotle
Aristotle didn’t want to believe that the world could be a system of atom as Democritus said. Instead of believing in atoms he believed in Earth, Air, Fire, and Water. Which those four elements are what creates everything around us and was believed as the base of life. From Aristotle believes he spread a lot of false information for over 2,000 years. -
300 BCE
Alchemy
After Alexander the Great conquered Egypt, some Greek philosophers became very interested in the Egyptian religion. The Greeks believed that matter was made from the four elements(Earth, Water, Fire, and Air) and these were merged with Egyptian religions. The result of this was Khemia, which is the Greek word for Egypt. The word Alchemy comes from the word Khemia. In 600 A.D. Egypt was occupied by Arabs who would further developed the science and spread it to the west. -
300 BCE
Alchemy part 2
Eventually, by the 16th century, the alchemists in Europe had separated into two groups. In the west, alchemists focused on the discovery of new compounds,reactions,and chemical processes leading to what is now the science of chemistry. The west also created very important things like they Invented distillation, percolation, extraction, rudimentary chromatography and these different things have been very important even until today. The other group decided to look for more spiritual ways. -
300 BCE
Alchemy part 3
The second group continued the search for more immortality and he transmutation of base metals into gold. This led to the modern day idea of alchemy. -
300 BCE
Vitalism
Vitalism states the living organisms are different from non-living organisms because they contain a “vital spirit”. The vital sprit is kinda like a substance that infused into the body and gives them life. The vital spirit can be seen as like a soul. This creates that living things are thus governmenes by different principles than inaimwte things. -
The Phlogiston Theory
This is a theory that a fire-like element called phlogiston is contained within combustion bodies and released during combustion. This name comes from the Greeks phlogiston(burning up). Johanna Joachim Becher first started this in 1667 but was put together more by Georg Stahl. The theory states that phlogistcated substance are substance that contain phlogiston and dephlogisticate when burned. Carbon Dioxide that can no longer be capable of burning is called dephlogisticated air. -
Anton Laurent de La Voisier
Antoine Lavoisier was a French nobleman and chemist.He was know for being the Father of Modern Chemistry because he relied on quantitative observations to develop conclusions. Lavoisier also was noted for his discovery of the role oxygen plays with combustion. Lavoisier also discovered the Law of Conservation of Mass. This law states that that the mass of a metal oxide=the mass of the metal plus oxygen when the metal oxide decomposes. -
Anton Laurent de La Voisier part 2
Matter can change form but cannot be created or destroyed In a chemical reaction. He was also beheaded during the French Revolution. -
Benjamin Franklin
Benjamin Franklin was an American polymath and one of the founding fathers of the United States. Franklin can be found on the one hundred dollar bill. Benjamin Franklin was extremely intelligent and He only had two years of formal education and became a hit writer as a teenager. Benjamin also discovered that electrical charges comes in two varieties- positive and negative. Like charges repel, opposite charges attract. -
Joseph Louis Proust
Joseph Louis Proust was a French chemist who was best know for the discovery of the Law of Constant Composition. The Law of Constant Composition states that a chemical compound always contains exactly the same proportion of the elements by mass. -
John Dalton
John was an English chemist, physicist, and meteorologist. John Dalton was the Father of the Atomic Theory. This Theory states that matter is made up of atoms that are indivisible and indestructible, all atoms of an element are identical (which has been proven wrong), atoms of different elements have different weights and different chemical properties, atoms of different elements combine in simple whole numbers to form compounds, and atoms cannot be created or destroyed. -
William Crookes
William Crookes was a British chemist and physicist who created the Cathode Ray Tube. The Cathode Ray Tube is a glass tube that is evacuated (contains no air or matter) coated with fluorescent paint. When connected to a battery the paint glows, indicating that there is some type of radiation streaming from the battery(the cathode). William also created the paddle wheel placed in CRT. When Crookes place a paddle wheel in the CRT and turned on the battery, the wheel spun. -
Sir John Joseph Thomson
Sir John Joseph Thomson is best know for being the man who discovered electrons. J.J. Thomson was born on December 18, 1856, in Cheetham Hill, England, where he would grow up to become a physicist and discovered many things. He continued experimenting on the CRT. J.J. Thomson used charged plates to deflect the cathode rY. Found the ray deflected away from the negative plate, and towards the positive. He found the negative particles and named them electrons. -
Ernest Rutherford
Ernest Rutherford identified the nature of alpha and beta radiations. He connected alpha radiation to helium and then later identified the, to helium nuclei. Then a few years later interpreted beta particles as electrons. Rutherford was also famous for the the gold foil experiment. He stretched a sheet of gold foil in a tin can and coated the inside of the can with fluorescent paint. Aimed a ray of alpha radiation (+charges) at the foil. -
Curies (Marie and Pierre)
The Curies were Polish French physicist and chemist who did research on radioactivity. They discovered and isolated polonium and radium from uranium ore. -
Becqueral
Antoine Henri Becquerel was a French engineer, physicist, and was the first person to discover evidence of radioactivity. He discovered radioactivity in Uranium ore. -
Millikan
Robert Andrews Millikan was honored with the Noble Prize for Physics in 1923 for calculating the mass and charge of an electron and for his work on the photoelectric effect. -
Ernest Rutherford part 2
Rutherford also observed 99.9% of the time, the Ray lit up the can right behind the foil, .1% of the time, the Ray lit up the can opposite the foil, and this told him that the Ray had hit something massive and dense in the center of the atom. He deduced atoms are mostly empty space, there must be a solid core in the center of the atom, and the core must be positively charged, since it deflected an alpha Ray. -
James Chadwick
Proved the existence of another subatomic particle, that had no charge, named it the neutron
