1. Acids
and
Bases

2. Vocab Acid…produces H+ ions in water Base…produces OH- ions in water
Buffer…a substance added to minimize the affects on pH
Hydronium ion…H30+
Indicator…changes color in acids/bases

3. Neutralization…chemical reaction that takes place between an acid and base in water
pH…measure of H+ concentration
Salt…formed with the + ion from the base and - ion of the acid
Soap…organic salts

4. Strong acid…ionizes almost completely in water
Strong base… acid…ionizes almost completely in water
Titration…used to determine the concentration of an unknown
Weak acid… does not ionize completely in water
Weak base…does not ionize completely in water

5. HCl + H2O  H3O+ + Cl– Acids Definition of an acid
Ionize to form hydronium ions (H3O+) in water
HCl + H2O  H3O+ + Cl–

6. Acids
All acids have at least one hydrogen that can be removed when added to water.
The hydrogen ions, H+, react with water to form hydronium ions, H3O+
Can burn tissue.
React with indicator paper to produce a predictable color change. Ex. Litmus turns red in acid.

7. Properties ACIDS BASES sour taste corrosive electrolytes
turn litmus red
react with metals to form H2 gas
bitter taste
corrosive
electrolytes
turn litmus blue
slippery feel

8. ACIDS Common acids: Citric acid Lactic acid Acetic acid
Examples:
H3PO4 - soft drinks, fertilizer, detergents
H2SO4 - fertilizer, car batteries
HCl - gastric juice
HC2H3O2 - vinegar
Common acids:
Citric acid
Lactic acid
Acetic acid
Hydrochloric acid

9. Bases NH3 + H2O  NH4+ + OH- Definition of a Base
Dissociate or ionize to form hydroxide ions (OH-) in water
NH3 + H2O  NH4+ + OH-

10. BASES Examples: NaOH - lye, drain and oven cleaner
Mg(OH)2 - laxative, antacid
Common bases:
Ammonia
Milk of magnesia
Baking soda
Soap

11. Form hydroxide ions, OH-, in water. Accepts hydrogen ions from acids.
Bases
Form hydroxide ions, OH-, in water.
Accepts hydrogen ions from acids.
Turn litmus paper blue.

12. Acids and Bases Acids produce H+ in aqueous solutions
water
HCl H+(aq) + Cl- (aq)
Bases produce OH- in aqueous solutions
NaOH Na+(aq) + OH- (aq)

13. Strength of Acids and Bases
The ability of an acid or base to ionize in solution affects its strength.
An acid that ionizes almost completely is a strong acid.
H2SO4 and HCl are examples.
An acid that only partially ionizes is a weak acid such as carbonic or acetic.

14. Concentrated vs Dilute
You can have dilute solutions of strong or weak acids and bases.
This is not weak or strong!

15. The measure of hydrogen ion concentration
What is the pH scale?
The measure of hydrogen ion concentration
The more H ion, the greater the acidity.

16. What is the pH scale?
The pH scale measures how acidic or basic a solution is.

17. Identifying Acids and Bases
Acids have a ph from 0-7
Lower pH value indicates a stronger acid.
Bases have a pH from 7-14
Higher pH value indicates a stronger base.
**Acids and bases react together in a NEUTRALIZATION reaction

18. A pH level of 7 indicates a Neutral Substance aka WATER!
Neutral pH
A pH level of 7 indicates a Neutral Substance aka WATER!

19. Working with Indicators
Red litmus turns BLUE in the presence of Bases
Blue litmus turns RED in the presence of acid
Acids and bases react together in a NEUTRALIZATION reaction
Lesson 5/6
Demo frothing rainbow (KISS)??????????????????
Draw on board word equation Reactants -- Products, Acid + base --- salt + water eg HCl + NaOH - NaCl + H2O
ALWAYS OBSERVE WHEN MIXING CHEMICALS SMELL< FIZZ< HEAT< COLOUR ETC
EXPT H/O indicators worksheet work in groups (make own indicator)
EXPT find Ph of everyday substances H/O WRITE UP CORRECTLY, conclusion BLUE ALKALI, RED ACID< GREEN NEUTRAL

20. Titration
standard solution
unknown solution
Titration
Process in which a standard solution is used to determine the concentration of an unknown solution.