ATOMIC STRUCTURE

ATOMIC STRUCTURE

1. ISOTOPES

2. PERIODIC TABLE

   • Arranged in order of atomic number
   • Groups are vertical rows
   • Periods are horizontal rows

3. COMPOUNDS

   • 2 or more chemically bonded elements
   • Possess different chemical and physical elements from the elements they were made from
   • Ionic compound: Thousands of ionic bonds electrostatically attracted to each other

4. IONS

   • Created during a chemical reaction
   • Atom wants to get a full outer shell
     • Stable
   • Cations = positive ions
     • Named after the element they are formed from. E.g calcium ion (Ca2+)
   • Anion = negative ions
     • Named using the suffix - ide. E.g. choride and oxide
   • Polyatomic ions
     • Ions made of many atoms
       • Named using the suffix - ate
   • An atom or group of atoms that have lost or gained electons

5. ELECTRONS

   • Orbit the nucleus of an atom
   • First level = max 2 electrons
   • Second level = max 8 electrons
   • Third level = max 8 electrons

6. PROTONS AND NEUTRONS

   • Proton number = neutron number
   • Electron number = proton number
   • neutron number = mass number - atomic number
   • Atomic mass = the number of protons + neutrons determines the mass of an atom
   • Atomic number = the number of protons in an atom