Ch. 3 - pH
Rate is low # of hydronium ions = # of hydroxide ions Dissociation of water
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
(H + )(OH - ) = pH = -log(H+) If (H + ) is then the –log10 -7 = -(-7) = 7 ***pH declines as (H + ) increases Ex) A solution with a pH of 10 (H+) = and (OH) = ****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
1. Which is more acidic? (H+) of 1.0 x or 1.0 x 2. Which is more basic? (H+) of 1.0 x or 1.0 x 3. What is the H+ concentration of stomach acid? Practice
(H3O+) or (H+)Scientific notationpH More practice
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