HeavenS

1. There were many important scientists who contributed to our current knowledge of the atom. Some of these scientists include Lise Meitner Hahn, she lived in 1938, and she conducted experiments verifying that heavy elements capture neutrons and form unstable products which undergo fission, Isaac Newton lived in 1704 and he proposed a mechanical universe with solind masses in motion, John Dalton, who lived in 1803, proposed an atomic theory with spherical solid atoms based upon measurable properties of mass, and Micheal Faraday, who lived in 1832, studied the effect of the electricity on solutions and developed laws of electrolysis. J.Plucker lived in 1859 and built one of the first gas discharge tubes ("cathode ray tube").



2. There were many important experiments that were used to make breakthrough discoveries. Joseph John Thomso conducted cathode ray tube experiments in 1897 and discovered the electron and its negative charge. Ribert Millikan's oil-drop experiment suggested that electric charge occurs as quanta in 1909. Ernest Rutherford conducted a gold foil experiment in 1911 and demonstrated that the positive charge and mass of an atom is concentrated in a small, central atomic nucleus, disproving the then-popular plum pudding model of the atom. Enrico Fermi split the atom in 1934, and Clyde L. Cowan and Frederick Reines confirmed the existance of the neutrino (elementary particle) in the neutrino in the neutrino experiment in 1955. There are many other discoveries and experiments used to find out what we know today about the atom, but these are some of the most important, and influential ones.



3. The central portion of an atom is known as the atomic nucleus. It consists of protons, which carry positive charge and neutrons, which carry no electric charge. The negatively charged electrons orbit the atomic nucleus. The protons and neutrons in an atomic nucleus contribute to the atomic mass. However, the electrons floating in the region around the nucleus are extremely lightweight subatomic particles. Atoms get together to form molecules. When atoms of different elements come together, compound molecules are formed. As you might know, there are two types of compounds, ionic and covalent. The ions of ionic compounds are bound together due to the electrostatic forces between oppositely charged bodies. When atoms share pairs of electrons to form chemical bonds, they are known as covalent compounds. Chemical reactions between atoms of different elements result in the formation of complexly structured compounds.



Bibliography: [] [] []