0h 16min, jan 1, 400 y BC - Democritus (400 BC)

Description:

Greek philosopher Democritus (460 BC-370 BC) formulates the precursor to atomic theory by cutting objects as small as he could cut them. He called the small objects "atoms," derived from the Greek word "atomos," meaning indivisible, because the objects were simply too small to be cut any further. However, the belief of the day was that the only four elements were Earth, air, fire, and water. Due to Democritus's beleifs, he was rejected from the philosophical community of the day.

His 5 principles of atoms are as follows:

1.)Matter is composed of atoms separated by empty space through which atoms move.

2.)Atoms are solid, homogeneous, indivisible, and unchangeable.

3.)All apparent changes in matter result from changes in grouping of atoms.

4.)There are different types of atoms that differ in size and shape.

5.) The properties of matter reflect the properties of the atoms the matter contains.

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