1. Warm-Up
What is an acid?
What is a base?

2. Warm-up
How many grams of potassium chloride are needed to prepare 0.750L of a 1.50 M solution of potassium chloride in water?

3. Acids & Bases

4. Acid Properties Affect the color of indicators
Neutralize bases to form water
Acid (aq) + Base (aq)  Salt (aq) + H2O (l)
React with metals to produce hydrogen gas
Metal (s) + Acid (aq)  Salt (aq) + H2 (g)
Taste sour
Ex: Citric Acid (C6H8O7)

5. Acid Strength
Strong acids completely dissociate in water, meaning all the molecules become ions
HCl (aq) + H2O (l)  H3O+ (aq) + Cl- (aq)
7 of these: HCl, HBr, HNO3, H2SO4, H3PO4, HClO3 HClO4
Weak acids do not dissociate easily, meaning only a few molecules become ions
HC2H3O2 (aq) + H2O (l) ↔ H3O+ (aq) + C2H3O2- (aq)
Common: H2CO3, HC2H3O2
H3O+ = Hydronium ion, same thing as H+ (aq)

6. Base Properties Affect the color of indicators
Neutralize acids to form water
Feel slippery
Ex: Soaps
Taste bitter
Ex: Green vegetables

7. Base Strength Strong bases produce hydroxide ions in a solution
Ca(OH)2 (aq)  Ca2+ (aq) + 2 OH- (aq)
Ex: CaO, NaOH, KOH, Ca(OH)2
Weak bases do not dissociate in solution
Ex: NH3, CO32-, ClO-

8. *Note
H3O+ = hydronium ion, same thing as H+(aq)

9. Types of Acids & Bases Arrhenius Brønsted-Løwry
Acid – a substance that can donate an H+ ion
Base – any substance that can accept an H+ ion (has a lone pair)
Acid – a substance that can donate an H+ ion when dissolved in water
Base – a substance that can donate an OH- ion when dissolved in water

10. Conjugate Pairs
Pairs that differ by only one proton (H+) are called conjugate pairs
A strong acid will make a weak conjugate base
A weak acid will make a strong conjugate base
Reversible reactions have an acid and base on both sides
Reaction equilibrium will favor the side with the weaker acid and base

11. Warm-Up
How many grams of sucrose (C12H22O11) are dissolved in 287 mL of solution if the solution concentration is M?

12. Chemistry Molarity Worksheet – turn in to ME (not the inbox)
Complete pre-lab and turn in to ME
Complete conjugate pair worksheet

13. Warm-Up What are the conjugate bases of these acids? HI HSO4- H2CO3
HPO42-

14. pH Scale
pH is a measurement of the concentration of H+ ions in solution
pH = -log[H+] [H+] = 10-pH
pOH is a measurement of the concentration of OH- ions in solution
pOH = -log[OH-] [OH-] = 10-pOH
In pure water, pH and pOH are both 7
Kw = [H+][OH-] = 1 x 10-14
pH + pOH = 14

15. pH Conversions

16. Practice
If [H+] = 1.0 x 10-7 M, then what is the pH?
pH = 7.0

17. Practice
If [OH-] is 5.01 x 10-4 M, what is the pOH?
pOH = 3.30

18. Practice If [OH-] is 5.01 x 10-4 M, what is the pOH?
If we had been given the pOH and we were asked to calculate the [OH-] what would you do?
pOH = 3.30

19. Practice
In household bleach, the concentration of OH- ions is 5.0 x 10-2 M. What is the pH?
pOH = 1.3
pH = 12.7

20. pH Indicators
Litmus Paper
Universal Indicator

21. Titration Curves
Equivalence point is equal to 7 for strong acid + strong base.

22. Titration Curves
Equivalence point is less than 7 for strong acid + weak base
Equivalence point is greater than 7 for weak acid + strong base

23. pH Indicators
Methyl Red
Bromothymol Blue
Phenolphthalein