Atoms and Chemical bonds

• Democritus


  developed an atomic model which states that the universe and all matter obey the following principles:

  • Everything is composed of "atoms", which are physically indivisible
  • Between atoms, there lies an empty space; a void
  • Atoms are indestructible
  • Atoms have always been and will always be in motion
  • There are an infinite number of atoms
• Dalton's atomic theory

  • atoms make up all matter
  • atoms differ in their masses
  • atoms are neither created nor destroyed
• All matter is composed of atoms
• Atoms

  the smallest particles that constitute elements and cannot be split by chemical means