1. Ch. 3 - pH

2.  Rate is low  # of hydronium ions = # of hydroxide ions Dissociation of water

3.  Substance that increases (H+) = acid  Ex) HCl  H + +Cl-  Substance that reduces (H + ) = base  Ex) NH3 + H +  NH4 or NaOH  Na + + OH -   Acids and Bases

4.  (H + )(OH - ) = 10 -14  pH = -log(H+)  If (H + ) is 10 -7 then the –log10 -7 = -(-7) = 7  ***pH declines as (H + ) increases  Ex) A solution with a pH of 10  (H+) = 10 -10 and (OH) = 10 -4  ****each pH unit represents a tenfold difference in H+ and OH- concentration  Ex) Sol’n A (pH 3) vs Sol’n B( pH 6)  Solution A is 1000 times mores acidic than Solution B pH scale

5.  1. Which is more acidic? (H+) of 1.0 x 10 -8 or 1.0 x 10 -12  2. Which is more basic? (H+) of 1.0 x 10 -6 or 1.0 x 10 -3  3. What is the H+ concentration of stomach acid? Practice

6. (H3O+) or (H+)Scientific notationpH 0.1 0.01 0.001 0.0001 0.00001 0.000001 0.0000001 0.00000001 0.000000001 0.0000000001 More practice

7.  As (H+) gets smaller, scientific notation exponents get bigger, and pH goes up.  As (H+) gets larger, scientific notation exponents get smaller, and pH goes down. Summary