Acid Base pH Math   *   What is the actual Hydrogen Ion Concentration, or pH?  What is the pOH^- ?

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Mathematically,  pH = -log [H⁺]  which means, the negative log of the hydrogen ion concentration.
Neutral is when there are NO hydrogen ions, or hydroxides.  Neutral is also when these ions equal each other, [H⁺] = [OH^-]

When the pH is 7.0, neutral, and the two ion concentrations are equal to each other,  the [H⁺] = 1 x 10^-7 mol/L concentration. 

The [OH-] is also 1 x 10^-7 mol/L concentration.   The pH + pOH exponents combine to 14.  In this drill, for each pH & each pOH, decide what the ion concentrations are.  Casually, see how the exponents total 14 for each pH/pOH pair. 

What is the Mathematical expression for the ion concentrations for these pH/pOH values? 

A 

pH 1.0    [H⁺] = 1 x 10^-1                 [OH^-] = 1 x 10^-13

                   ^{relatively large number                                           very small number}

             ^{strong acid, lots of hydrogen ions, almost no hydroxide ions}

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B 

pH 12.0    [H⁺] = 1 x 10^-12                 [OH^-] = 1 x 10^-2

                      ^{very small number                                           relatively larger number}

             ^{strong base, few hydrogen ions, many hydroxide ions}

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C 

pH 6.5    [H⁺] = 1 x 10^-6.5                 [OH^-] = 1 x 10^-7.5

                               ^{nearly equal to  hydroxide value                              nearly equal to hydrogen ion value}

     weak acid, hydrogen ions only in slightly greater amount than hydroxide ions

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D

pH 9.0    [H⁺] = 1 x 10^-9                 [OH^-] = 1 x 10^-5

                      ^{very small number                                           relatively larger number}

     medium strength base, not many hydrogen ions, many more hydroxide ions

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E

pH 2.2    [H⁺] = 1 x 10^-2.2                 [OH^-] = 1 x 10^-11.8

                      ^{relatively large number                                           fairly small number}

          ^{strong acid, lots of hydrogen ions, few hydroxide ions}

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F

pH 10.1    [H⁺] = 1 x 10^-10.1                 [OH^-] = 1 x 10^-3.9

                         ^{fairly small number                                           fairly larger number}

               pretty strong base, fewer hydrogen ions, lots of hydroxide ions

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G

pH 4.0       [H⁺] = 1 x 10^-4                 [OH^-] = 1 x 10^-10

                     ^{relatively larger number                                           relatively smaller number}

          medium strong acid, many hydrogen ions, not so many hydroxide ions

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H

pH 14.0    [H⁺] = 1 x 10^-14                 [OH^-] = 1 x 10⁰

                             ^{very, very small number                                           relatively huge number}

            ^{strong base, almost no hydrogen ions, maximum hydroxide ions}

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