1. Acids & Bases

2. What is an acid?
An acid is a solution that has an excess of H+ ions. It comes from the Latin word acidus that means "sharp" or "sour".
The more H + ions, the more acidic the solution.

3. Properties of an Acid Tastes Sour Conduct Electricity
Corrosive, which means they break down certain substances. Many acids can corrode fabric, skin,and paper
Some acids react strongly with metals
Turns blue litmus paper red
Picture from BBC Revision Bites

4. Uses of Acids Acetic Acid = Vinegar
Citric Acid = lemons, limes, & oranges. It is in many sour candies such as lemonhead & sour patch.
Ascorbic acid = Vitamin C which your body needs to function.
Sulfuric acid is used in the production of fertilizers, steel, paints, and plastics.
Car batteries

5. What is a base? A base is a solution that has an excess of OH- ions.
Another word for base is alkali.
Bases are substances that can accept hydrogen ions

6. Properties of a Base Feel Slippery Taste Bitter Corrosive
Can conduct electricity. (Think alkaline batteries.)
Do not react with metals.
Turns red litmus paper blue.

7. Uses of Bases
Bases give soaps, ammonia, and many other cleaning products some of their useful properties.
The OH- ions interact strongly with certain substances, such as dirt and grease.
Chalk and oven cleaner are examples of familiar products that contain bases.
Your blood is a basic solution.

8. The pH scale is a way of expressing the strength of acids and bases
The pH scale is a way of expressing the strength of acids and bases. Instead of using very small numbers, we just use the NEGATIVE power of 10 on the Molarity of the H+ (or OH-) ion. Under 7 = acid 7 = neutral Over 7 = base

9. pH Scale
A change of 1 pH unit represents a tenfold change in the acidity of the solution.
For example, if one solution has a pH of 1 and a second solution has a pH of 2, the first solution is not twice as acidic as the second—it is ten times more acidic.

10. Acid Nomenclature Review
No Oxygen
w/Oxygen
An easy way to remember which goes with which…
“In the cafeteria, you ATE something ICky”

11. Acid/Base definitions Definition 1: Arrhenius
Arrhenius acid is a substance that produces H+ (H3O+) in water
Arrhenius base is a substance that produces OH- in water
4.3

12. Acid/Base Definitions
Definition #2: Brønsted – Lowry
Acids – proton donor
Bases – proton acceptor
A “proton” is really just a hydrogen atom that has lost it’s electron!

13. Strong and Weak Acids/Bases
The strength of an acid (or base) is determined by the amount of IONIZATION.
HNO3, HCl, HBr, HI, H2SO4 and HClO4 are the strong acids.

14. Strong and Weak Acids/Bases
Generally divide acids and bases into STRONG or WEAK ones.
STRONG ACID: HNO3 (aq) + H2O (l)  H3O+ (aq) NO3- (aq)
HNO3 is about 100% dissociated in water.

15. Strong and Weak Acids/Bases
Weak acids are much less than 100% ionized in water.
*One of the best known is acetic acid = CH3CO2H

16. Strong and Weak Acids/Bases
Strong Base: 100% dissociated in water.
NaOH (aq)  Na+ (aq) + OH- (aq)
Other common strong bases include KOH and Ca(OH)2.
CaO (lime) + H2O -->
Ca(OH)2 (slaked lime)
CaO
Strong bases are the group I hydroxides
Calcium, strontium, and barium hydroxides are strong, but only soluble in water to 0.01 M

17. Strong and Weak Acids/Bases
Weak base: less than 100% ionized in water
One of the best known weak bases is ammonia
NH3 (aq) + H2O (l) ↔ NH4+ (aq) + OH- (aq)

18. Acid – Base Reactions
A reaction between an acid and a base is called neutralization. An acid-base mixture is not as acidic or basic as the individual starting solutions.

19. Acid – Base reactions
Each salt listed in this table can be formed by the reaction between an acid and a base.