History of the Atom

Democritus

465

Democritus was the first person to think of the Atom, this is why he was very important. Democritus also thought that atoms were industructable. His hypothesized that atoms cannot be destroyed, differ in size, shape, and tempurature. His other thought was that there are an infinitive number of atoms. This hypothesis was created in 465 BC.

Dalton

Sep 30, 1803

Dalton was the first person to think that every gas, liquid, and solids had atoms. He thought of compound atoms. Compound atoms is when a substance is formed by two or more chemical elemnts that are chamically bonded together. All of his laws he made were law of conservation of mass, law of definite porportions, law of multiple porportions. He infered that atoms had certain characteristics. This is important because it helps us understand atoms more. He discovered this in 1803.

Thomson

May 28, 1897

Thomson discovered the electrons. He also studied positively charged particles in neon gas. He realized that the accepted model of the atom did not account for negatively and positiively charged particles. This is important because we know that electrons must have some kind of positive charge to balance out th negative charge in the electrons.

Rutherford

Oct 31, 1911

Rutherford was a former student of Thomson. Rutherford proved Thomson's structure of the atom was incorrect. Rutherford showed an experiment that proved Thomson wrong. He discovered the nucleus which was very impotant to upcoming the science world. He concluded that the atom consisted of small, dense, positvley charged nucleus in the center with negativley charged electrons around it.

Bohr

Dec 25, 1913

Bohr was a student of Rutherford and he developed a new model of the atom. This was important because it was a more accurate model of the atom. Electrons onl go around certain parts of the nucelus and some orbits are stationary. His model was more complex and it is know as the planetary model because it represented the solar system.

Schrodinger

Mar 20, 1926

He was an Austrian side kick. He took Bohr's atom model one step forward. He used mathmatical equations to describe the likleyhood of finding an electron in it's exact position. The atomic model is know as the quantum mechanical model. This predicts the odd of the location of the electron.

Chadwick

Dec 13, 1932

Chadwick showed that there is another part of the atom called the neutron. He discovered it. This is important because many other scientist have learned more about the atom sense then. An unknown radius was produced from his model, He thought this radiation was made of neutral electrical charges.