1. A. Acids and Bases The Arrhenius Model
Acid – produces hydrogen ions in aqueous solution
Base – produces hydroxide ions in aqueous solution
Macid * Vml (acid) = Mbase * Vml (base)
Mbase * Vml (base) = Macid * Vml (acid)
Macid = Mbase * Vml (base) Mbase = Macid * Vml (acid)
Vml (acid) Vml (base)

2. The Bronsted-Lowry Model
Acid – proton donor
Base – proton acceptor
The general reaction for an acid dissolving in water is

3. The Bronsted-Lowry Model
Conjugate acid-base pair

4. The Bronsted-Lowry Model
Water acts as a base accepting a proton from the acid.
Forms hydronium ion (H3O+)

5. B. Acid Strength
Strong acid – completely ionized or completely dissociated

6. Weak acid – most of the acid molecules remain intact

7. A strong acid contains a relatively weak conjugate base.
A weak acid contains a relatively strong conjugate base.

8. Common strong acids are
Sulfuric acid, H2SO4
Hydrochloric acid, HCl
Nitric acid, HNO3
Perchloric acid, HClO4

10. C. Water as an Acid and a Base
Product of [H3O+] and [OH] is always constant.

11. *

12. [ ] = molarity D. The pH Scale
The “p scale” is used to express small numbers.
pH = log [H+]
[ ] = molarity

13. *

14. Because the pH scale is a log scale based on 10, the pH changes by 1 for every power of 10 change in the [H+].

15. D. The pH Scale *

16. pOH scale
pOH = log [OH]
pH + pOH = 14.00

18. *
E. Measuring pH
Indicators – substances that exhibit different colors in acidic and basic solutions
In an acid solution the indicator will be in the HIn form.
In a basic solution the indicator will be in the In form.

19. F. Acid-Base Titrations
Titration – delivering a measured volume of a solution of known concentration into the solution being analyzed
Titrant – a standard solution
Buret – device used for accurate measurement of the delivery of a liquid
Stoichiometric point (equivalence point) – when just enough titrant has been added to react with all of the solution being analyzed

20. Titration curve (pH curve) – plot of the data (pH vs volume) for a titration*

21. G. Buffered Solutions
Buffered solution – resists a change in its pH when either and acid or a base has been added
Presence of a weak acid and its conjugate base buffers the solution

23. Titration