iv. ATOMS

Atom

• the basic unit of matter.

Nucleus

• center of the atom.

Subatomic Particles

• smaller than atom, smallest particle.

Particles

• the fundamental building blocks.
  - tiny, discreet.

  • e.g. molecules, ions.

Thales

• proposed that water was the primary substance of everything.

Anaximenes

• thought that the air was the fundamental substance.

Heraclitus

• theorized fire (constantly changing) as the main substance.

Aristotle

• suggested that water, air, fire, and earth.

Water

• when the material flowed,

Fire

• when it emitted flames and heat,

Air

• if it was light and invisible,

Earth

• when it was solid and heavy,

Democritus

• matter was made up of extremely tiny particles, “atomos” (indivisible)

• can combine;

  • and different arrangements meant different materials.

Atomos

• means “indivisible.”