1. Acids and Bases

2. Acids and Bases: Classification
Nothing itself can be an acid or base
Must be dissolved in water
Behavior in water determines whether a substance is an acid or base
Acids = H + elements (ex: HCl)
Produces Hydrogen ions (H+) in solution
Base = Element + OH (ex: NaOH)
Produce hydroxide ions (OH-) in solution

3. Quick Side note about H+
H+ ions are also referred to as H3O + ions.
Why is that?
Remember that acids must be in solution, which means dissolved in water.
When in water, the H+ ions attach to H2O, producing H3O +
So as H+ increases, H3O + is also increasing

4. Acids: form H+ ions in solution (Or H3O)
Properties:
Conducts electricity when in solution
Corrosive
Taste sour
React with metals
Examples:
Citric Acid – OJ
Lactic acid – milk
Acetic acid - vinegar
Nitric acid – fertilizers
Folic acid – green vegetables

5. Bases: form –OH ions in solution
Properties:
Slippery to touch
Electrolytes: conduct electricity in solution
Taste Bitter
corrosive
Examples:
Bleach
Sodium Hydroxide – Baking Soda
Ammonia
Soap
Cleaners

6. pH of Solutions
Scale from 0 to 14
0-6 range indicates acids
7 is neutral
8-14 range indicates bases
A measure of the concentration of H+ ions in a solution
The more H+ ions in a solution, the more acidic it is, the lower the pH
Fewer H+ ions in solution, the more basic it is, the higher the pH

7. Strength of acids and bases
If 7 is neutral, the further away from 7 you get, the stronger your acid or base is.
HCl (pH 1) is much stronger an acid than a banana (pH 5)
Ammonia (pH 11) is much stronger than baking soda (pH 8)

8. Indicators Litmus Paper is an indicator. Standard Litmus Paper
Indicator is anything that allows us to visually tell the pH of a given substance
There are many different indicators
Standard Litmus
Paper
Red = acid
Blue = base
Stays yellow = neutral

9. Some indicator papers Some are natural Indicators
Standard Yellow Paper (0-14),
Blue Paper (0-7), Red Paper (7-14)
Some are natural
Cabbage Juice
Flowers

10. Neutralization
When equal strength acids and bases combine, the acidic and basic properties cancel out
Remaining ions form a salt and water
2 HCl + Ca(OH)2  CaCl H2O
acid base  salt water
If a strong acid is mixed with
a weak base, the resulting
solution is a weaker acid.

11. COMMON SALTS