atoms

• is anything that occupy space and has mass.

  matter
• All matter is made of ___

  atoms
• ____ are the basic building blocks of matter.

  atoms
• Three subatomic particles make up every atom:

  protons, neutrons, electrons
• The word atom came from the Greek word ____ which

  means "indivisible"

  atomos
• ___ are positive, have a mass roughly the same as a

  neutron, found in the nucleus, define an element


  protons
• ___ have no charge, have a mass roughly the same

  as a proton, found in the nucleus, are responsible for

  isotopes


  neutrons
• The___ ___r is the number of protons in the nucleus of an atom.

  atomic number
• ___ are negative, very small mass, smallest

  subatomic particle, found outside of the nucleus, are

  responsible for ions.

  electrons
• How to get the mass number of an element?

  protons + neutrons
• To find neutrons:


  mass number - protons
• What is the mass number of an element with 10 protons and 10 neutrons?

  20
• What is the mass number of an element with 36 protons and 48 neutrons?

  84
• are atoms of the same element with a different number of neutrons.

  ISOTOPES
• The number of protons for an atom __ changes.

  never
• The number of neutrons ___ change

  can
• ___ are atoms of the same element with a different number of neutrons.


  isotopes