1. ACIDS AND BASES a review

2. Arrhenius Acids and Bases Acids = H+, Bases = OH- Modified Acids = H3O+, Bases = OH-

3. Modified Arrhenius Uses the idea that the substance will react with water to form H3O+ instead of just H+

4. Formulas You NEED to Remember

5. Example What is the [OH-] in a solution with [H3O+] = 2.59x10 -4 mol/L?

6. Example 2 If 2.50g of NaOH were dissolved in water to produce 500mL of solution, what would be [H3O+] and [OH-], pH and pOH?

7. Example 3 A solution has pH = 5.75. What are the values of pOH, [H3O+] and [OH-]? pOH = 8.25 [H3O+] = 1.8 x 10 -6 M [OH-] = 5.6 x 10 -9 M

8. Neutralizations Acid + Base = Water + salt Modified hydronium + hydroxide = water

9. Strong Acids completely give up their H+ in solution (reacts completely to form H3O+) very low pH high conductivity fast reaction rate

10. Weak Acids partially react with water to form H3O+ medium to low pH low conductivity slow reaction rate

11. Strong Bases completely dissociate to form OH- in water very high pH high conductivity fast reaction rate

12. Weak Bases partially dissociates to OH- medium to high pH low conductivity (molecular) slow reaction rate

13. Measuring pH pH can be measured precisely using a pH meter or you could use an indicator

14. Example Separate samples of a solution of unknown pH cause the following acid base indicator colours Orange IV = yellow Bromothymol blue = blue Phenolphthalein = colourless What is the solution pH? Hint: use the indicator chart at the back of your workbook!

15. Polyprotic Substances contain more than one hydrogen (or hydroxide) in their compound formulas HxA or A(OH)x

16. polyprotics react multiple times with water i.e. H3PO4 + H2O in general, polyprotic acids (bases) are weak acids (bases) whose reaction with water decreases with each successive step