1. Physical Science
Acids, Bases, & pH

2. Memorize: quiz Friday!! Common Acids Common Bases
Hydrochloric acid (HCl)
Sulfuric acid (H2SO4)
Acetic acid (HC2H3O2)
Nitric acid (HNO3)
Citric acid (C6H8O7)
Sodium bicarbonate (NaHCO3)
Sodium hydroxide (NaOH)
Potassium hydroxide (KOH)
Calcium hydroxide (Ca(OH)2)
Magnesium hydroxide (Mg(OH)2)
Barium hydroxide (Ba(OH)2)
Ammonium hydroxide (NH4OH)

3. Acids Substances that dissociate in water to form ions
Hydrogen ions (H+) attach to water to form H3O+ (hydronium ion) – process is ionization
Examples:
Battery acid
Vinegar
Citric acid- lemons, limes
Carbonic acid – soda; acid rain

4. Properties of acids Taste Sour Conduct electricity
Some are strong, some are weak electrolytes
Indicators (blue litmus turns red)
React with hydroxides (OH-) to form water and salt
Usually starts with an ‘H’

5. Electrolyte – ions that conduct electricity
When in a solution, the solution is called an electrolytic solution
Nonelectrolyte – molecules that don’t conduct electricity
When in a solution, the solution is called a nonelectrolyte solution

6. Acids The ones in food are dilute Concentrated acids are dangerous
They can burn your skin and eyes
Strong acids ionize completely
All the H’s make hydronium
HCl + H2O  Cl- + H3O+
Makes lots of ions
Can be dangerous

7. Bases Ionizes in water to yield hydroxide ions (OH- )
Has OH- in it or takes an H off of water
Examples
KOH - in drain cleaner
NaOH - in drain cleaner
NH3- ammonia

8. Properties of bases Taste bitter Feel slippery
Can be strong or weak electrolytes
Indicators (turns red litmus paper blue)
React with acids to form water and a salt

9. Bases
KOH  K+ + OH-
Strong bases ionize completely and makes lots of ions
Are dangerous
NH3 + H2O NH4+ + OH-
Weak acids only make a few ions
Are dangerous if concentrated

10. How Acidic? More H3O+ is more acidic Measured with pH
Lower pH is more acidic
As H3O+ goes down, OH- goes up
Higher pH more basic
pH of 7 is neutral
Acidic
Neutral 7
Basic 14

11. pH Scale

12. pH Low pH is acid Lots of H3O+ Little OH- High pH is base Little H3O+
Lots of OH-

13. Neutralization Reactions
A type of double displacement reaction
A reaction b/w an acid and base
H3O+ + Cl- + Na+ + OH-  Cl- + Na+ + 2H2O
Salt and water is always a product of the reaction
Product will be neutral if the right amounts of strong acids and bases are added

14. Neutralization Reactions
As you add acid to a base the pH drops
As you add base to and acid the pH rises

15. Soap Water and oil don’t mix Water is polar Oil is nonpolar
Soap can dissolve in both oil and water
Made by mixing fats with lye (NaOH)

16. Soap C O-
CH3
CH2

17. Soap C O-
CH3
CH2
Hydrophobic non-polar end

18. Soap C O-
CH3
CH2
Hydrophilic polar end

19. C O-
CH3
CH2 _

20. A drop of grease in water
Grease is non-polar
Water is polar
Soap lets you dissolve the non-polar in the polar.

21. Hydrophobic ends dissolve in grease

22. Hydrophilic ends dissolve in water

23. Water molecules can surround and dissolve grease.
Helps get grease out of your way.

24. Detergents
Soaps react with minerals in hard water and form scum that doesn’t dissolve
Detergents have the same basic structure but have a sulfur at the end,
And start from petroleum
Dissolve in hard water

25. Household Uses
Antacids- Weak bases that neutralize excess stomach acid
Shampoo- made from detergents
Need to keep pH between 5 and 8 or it will make the hair dull
Citric acid keeps fruit from browning
Acidic marinades tenderize meats
Drain cleaners are strong bases