1. Definitions
   1. atomic mass
      1. mass of protons and neutrons
   2. atomic number
      1. no. of protons
         1. subatomic particles.jpg
   3. nucleon number
      1. no. of protons and neutrons
   4. relative isotopic mass
      1. mass of an atom of the isotope x 12 / mass of an atom of carbon-12
   5. isotopes
      1. have same no. of protons; different no. of neutrons
   6. empirical formula
      1. simplest ratio of no. of atoms in each element of a compound
   7. molecular formula
      1. actual no. of atoms of each element of a compound
   8. relative atomic mass
      1. average mass of atom of the element x 12 / mass of an atom of carbon-12
   9. relative molecular mass
      1. average mass of a molecule of substance x 12 / mass of an atom of carbon-12
   10. molar mass
       1. 1 mass of 1 mole of substance
2. Mass spectrometry
   1. measure relative atomic masses
      1. vapourisation
         1. sample must be GASEOUS
      2. ionisation
         1. one e-/atom removed by high stream e-
            1. + ion formed
      3. acceleration
         1. + ion accelerated to magnetic field
      4. deflection
         1. ions with small m/e deflected more
         2. ions with LARGE m/e deflected less
      5. detection
         1. + ions detected
   2. vacuum pump
      1. pumps air from inside
         1. doesn't affect speeding molecules
   3. mass spectrograph
      1. each isotope has separate peaks
      2. "h" of peak = relative abundance of isotope
   4. untitled.bmp
3. Formula
   1. no. of mole
      1. mass (in g) / Ar
      2. mass (in g) / Mr
      3. mv / 1000
   2. avogadro constant
      1. 6.02 x 10^23 particles/atoms/molecules/ions
   3. volume (in cm3 / dm3)
      1. at stp, v = 22.4 dm3
      2. at rtp, v = 24 dm3