1800-+1875

__John Dalton__ **  **- Date of Birth: Sept. 6, 1766 - Date of Death: July 27, 1844 - Country of Origin: England Since the early age of 15, John Dalton dedicated his life to teaching. At the age of 21, he started with his meteorological journal in which he kept all his observations. 7 years later, he presented his first paper on Daltonism, now known as color-blindness. After this, he wrote many other papers on weather, heat and the origin of springs and the properties of gases. From this research, he enunciated the law of Expansion of Gases. This research made Dalton start thinking about his greatest discovery on the atomic structure; he was the first one to turn it into a universal law of atomic theory. This made him very famous. From here on, he turned into the president of the Manchester Literary and Philosophical Society and he wrote more works. None of the works that Dalton did after his atomic theory were really worthy of him so his popularity started to drop and more and more of his works were not published. Dalton never married; he kept a daily schedule he rarely broke of lab work and tuition. The only times he did break it was when he visited London or Paris, and when he went to play bowling on Thursdays. In 1837 and 1838, Dalton got strokes, which left him, very frail. In May 1844, he fell from his bed and was found dead by his assistant. This Atomic Theory discovery, Dalton laid the basics of the analysis for modern chemistry. He found that the weight of many elements were in a similar patternt that was also proportinate. This, he thought, could then be turned into a table. From here he concluded that it was little particles that composed most things, and these particles were all the same or very similar, just arranged different for the differet items. He then thought about compounds and how they are formed from elements. His final conclusion was that all matter was formed from elements or compounds. Before Dalton, the basis of Chemistry was the ideas of the ancient greeks.**
 * __1800-1875__


 * __Dalton's Atomic Model__ **

**Dalton's Atomic Model cosists of little balls called atoms which form all the objects that can be seen. The atoms for each element is different yet all the atoms from the same element are identical. In the case of the model above, the red spheres is the oxygen atom and the silver spheres are the hydrogen atoms. Together the hydrogen and the oxygen atoms make water particles.** ** __Michael Faraday__ ** ** -Born on September 22, 1791 in Newington Butts, Surrey, England -Died on August 25 1867 in Hampton Court, Surrey, England ** The confirmation of the electrical nature of matter paved the way for the first theories about the structure of matter. Michael Faraday discovered electrolysis in 1832. He was the one who gave the first significant clue linking electricity to matter regarding the electric nature of atoms. Faraday’s discovery of electromagnetic rotary devices shaped the foundation of electric motor technology. Due to his hard work, electricity turns out to be possible for use in technology. ** ** Michael Faraday promulgated two laws of electrolysis: **
 * Michael Faraday was an English chemist and physicist who contributed to the fields of electromagnetism and electrochemistry. His discoveries in the field of physics were **** diamagnetism, electromagnetic **** induction and the laws of electrolysis.
 * - If a fixed amount of electricity is passed through a cell, it produces a fixed amount of a particular substance at the electrode. ** **- The number of moles of various substances liberated at an electrode by a fixed amount of electricity is in the ratio of fixed integers. **

-Died in Turin, Italy on July 9, 1856 Amedeo Avogadro is an Italian physicist who presented the hypothesis that equal volumes of gas at same pressure and temperature have the same number of particles. Based on his law, he was the first one to demonstrate that water is H2O (two atoms of hydrogen and one of oxygen). In tribute to his significant contributions, the number of molecules in one mole was named after him. Avogadro’s number (6.022 x 10 23 ) states that when the mass of a compound in is equal to the molecular weight, the total number of molecules is always the same, equal to 1 mole. This number is used to determine the results of chemical reactions and to calculate the exact quantity of substances produced during a chemical reaction. During Avogadro’s time, there was confusion concerning the relationship between atoms and molecules. For that reason, it was significant that he made this relationship clear. He stated that gases are made of molecules and that these molecules are composed of atoms. ** 
 * __Amadeo Avogadro __ **
 * -Born in Turin, Italy on August 9, 1776