1. By: Desarae Costanzo and Marisa Shettsline

2.  Born in England on September 6, 1766  British chemist, physicist, and meteorologist  Very smart- taught at a Quaker school at the age of 12  Studied color blindness and the atomic theory  Died from a stroke on July 27, 1844

3.  Five parts of Dalton’s theory  All matter is made up of atoms  Atoms of a given element are identical in size, mass, and other properties; atoms of different elements have different properties  Atoms cannot be subdivided, created, or destroyed.  Atoms of different elements combine in simple whole-number ratios to form chemical compounds.  In chemical reactions, atoms are combined, separated, or rearranged.

4.  Parts of Dalton’s theory were incorrect  Atoms are indivisible  Atoms of a given element are identical  Some parts of his theory are still held today  All matter is composed of atoms  In chemical reactions, atoms are combined, separated, or rearranged  Atoms combine in simple whole-number ratios

5.  Similarities-  They both believed the atom was invisible and indestructible  They both claimed that everything was made up of atoms  The difference is that Dalton had evidence and could perform experiments whereas Democritus' theory was a product of his mind

6.  He reacted nitric oxide and oxygen together to produce a third type of gas  Realized that Atoms of different elements combine in simple whole-number ratios to form compounds (Law of Multiple Proportions)