A mole is the amount of an element quivalent to its atomic weight expressed in grams.

1 mole of H (atomic weight 1) is 1 gram
1 mole of H2O (molecular weight 18) is 18 grams.

In pure water, the concentration of hydrogen ions is 0.0000001 moles per litre, or 10-7 moles per litre. The exponent is taken, inversed and indicates its acidity (neutral in this case.) The lower the pH#, the higher the concentration of Hydrogen atoms. A difference of one pH unit represents a tenfold difference in the concentration of Hydrogen ions.


  • Solutions above and below pH 1-14 are possible, but are almost never encountered.
  • Almost all chemistry in living things takes place between pH 6 and 8.
  • Maintainance of pH is done by buffers which either accept or donate H+ ions.
    • A major buffer in the human bloodstream is acid-base pair H2CO3-HCO3-. When H+ enters the bloodstream, HCO3- absorbs it, forming H2O and CO2.
    • When OH- is added, it combines with H+ to form H2O; more H2CO3 tends to ionize to replace the H+ as it is used.
I hope this ends the bickering. =)