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Joseph and Josh

Dear Josh, Hey,I live in Rome,Italy.Rome is a really cool place.It's food is unbelievable.Isn't Hong Kong in China? I guess I have experince online. I think we should work well and get a good model to get a good grade.

John Dalton was a teacher. He was familiar with the philosophical concept of atomism. Hey, i live in Hong Kong, Japan. We should do good together then you can come visit and eat some sushi!!!**
 * Dear Joseph,

Associates: Your assigned atomic model is: Dalton
Dear joseph, My name is Joshua Williams.As i said before iam from Rome ,Italy. It is great here after we finish our work maybe you could come visit. I like to fish, ride bikes, and play air soft. Well im going to start on my part on the project now. Bye, Joshua

It was in the early 1800s that **John Dalton**, an observer of weather and discoverer of color blindness among other things, came up with his atomic theory. John Dalton, a school teacher, was familiar with the philosophical concept of atomism. He thought about the structure of matter within the parameters of Boyle's definition of an element, his understanding of the law of definite composition, and the law of conservation of mass. Dalton published his atomic model under the title "A New System of Chemical Philosophy" in 1803. The principle aspects of Dalton's theory were: 1) All substances are composed of small, dense, indestructible particles called atoms. 2) Atoms of a given substance are identical in mass, size, and shape. 3) An atom is the smallest part of an element that enters into a chemical change. Atoms may combine, or combinations of atoms may break down, but the atoms themselves are unchanged. 4) When atoms form molecules, they unite in small whole-number ratios (1:1, 1:2, 2:3 The idea that atoms are indestructable is supported by the law of conservation of mass. The asser-tion that each element is composed of a particular kind of atom was based on Dalton's observation that properties of different elements were not the same. Experimental observations that a given compound always has a constant mass composition provided the basis for his postulate that atoms of elements must combine in definite units or portions when forming compounds. He was the first to prepare a table of relative atomic weights for 14 elements and chose hydrogen, the lightest element, as a standard for atomic mass. Dalton also assigned symbols to these elements and combined given symbols to represent compounds. In 1811, Dalton discovered another principle that further convinced him of the existence of atoms. He successfully used his atomic model to predict the law of multiple proportions - when two elements form a series of compounds, the masses of one element that combine with a fixed mass of the other are in the ratio of small whole numbers. Dalton's model remains a cornerstone of the modern atomic theory of matter. His atomic model was able to relate the idea of atoms to the measurable property of mass and provided generations of scientists with the experimental basis for testing and modifying his theory.