History of Development of the atom

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Early greeks believed that all was made of 4 : earth, air, fire, and water.Living things they reasoned must be some part fire because they are warm. They must also have some proportion of water since blood and other body fluids are . They tried to organize all matter this way. There were several problems with this . No matter how small you broke down some matter, it never looked like what it was made of. You could not bring something back to life by simply warming it. These early thoughts did get people thinking about what matter was made of.

Democritus was a Greek philosopher who that there must be some piece of matter that was the part that still had the same characteristics and properties of that thing. Legend has it he was walking on the edge of the beach near cliffs and saw cliffs, boulders, rocks, pebbles, and sand. He reasoned that something must exist that was the smallest bit of matter that still had the property of sand. He called that smallest bit of matter . He also suggested that atoms once created could not be and that they must last forever. He also suggested that the atoms of stone were unique and different than atoms of other matter. He gave us the general and the name for the atom.

Another pioneer in the of the idea of the atom was and English school teacher named John Dalton. He was a careful observer and worked mostly with gases. He developed four ideas about the atom:
1. All matter is made of atoms which cannot be apart. Atoms are like tiny billiard balls.
2. All atoms of a single are the same. Atoms of different elements are . Atoms of different elements have different masses.
3.Chemical cannot destroy atoms. They can combine with each other in new ways.
4.When elements react, the always react in the ratios. Compounds have set formulas that have small numbers.