1. 1 The Chemistry of Acids and Bases

2. 2 Acid and Base Scale Acids pH from 0 to 7 Neutral pH is 7 Base pH from 7 to 14 pH is a measure of hydrogen ion concentration pH = -log[H + ]

3. 3 Acids Have a sour taste. Vinegar, orange juice, lemonade. Donates an H+ Have a bitter taste. Feel slippery. Donates OH- Ammonia, detergents, bleach Bases

4. 4 Monoprotic vs. Diprotic Monoprotic- an acid that can donate only 1 proton to a base (HCl) Diprotic- an acid that has two ionizable hydrogen atoms in each molecule, such as sulfuric acid (H 2 SO 4 ) Effects titrations

5. 5 ACID-BASE REACTIONS Titrations What is a titration? H 2 C 2 O 4(q) + 2NaOH (aq)  Na 2 C 2 O 4(aq) + 2H 2 O (l) acid base Ionic SaltWater acid base Ionic SaltWater Oxalic acid, H 2 C 2 O 4 A common laboratory method of chemistry that is used to determine the unknown concentration of an identified acid or base

6. 6 HCl (aq) + NaOH (aq)  HOH (l) +NaCl (aq) When we add the two together what do we get? –Neutralization Reaction What is the equivalence point? –Equal moles of acid and base Acid + Base 

7. 7 Titration 1. Add known solution to unknown solution to determine concentration. 2. Phenolphthalein indicator shows the equivalence point. (Acid = Base) This is called NEUTRALIZATION. This is called NEUTRALIZATION.

8. 8 35.62 mL of NaOH is neutralized with 25.2 mL of 0.0998 M HCl by titration to an equivalence point. What is the concentration of the NaOH? M a V a = M b V b (0.0998 M) (25.2 mL) = 0.0706 M (35.62 mL) Standardization of a solution of NaOH

9. 9 Practice a.35.0 b.1.12 c.25.8 d.62.4 e.39.3 In a titration of 35.00 mL of 0.737 M H 2 SO 4, __________ mL of a 0.827 M KOH solution is required for neutralization.

10. 10 Reminders Homework: Titrations WS Read through lab Reminders: Parent Letter DUE – bring in ASAP Extra Credit Due Friday (5/11) Thermo Test Corrections Due Thursday (5/10) at 8:30 am Sig Figs Redemption Thursday (5/10) at 7:30 am

11. 11 Wednesday and Thursday May 9 and 10

12. 12 Review Homework

13. 13

14. 14 What is too pink?

15. 15 The Stopcock Closed Open

16. 16 The Meniscus Read “upside down” Use paper to help see line

17. 17 More Hints Label beakers (tape on hood) Use paper to see color change

18. 18 Acid or Base and Skin Severity will vary with concentration, but BE SAFE, NOT SORRY!! Rinse skin IMMEDIATELY and call for Ms. Bjorge

19. 19 Standardization of a Base Lab Wear goggles and aprons If I have to tell you once to put them on you are out with a ZERO! Leave Buret in holder You will have to do multiple trials (as many as 10) Lab “write up” due BEGINNING of the period on Friday

20. 20 Done in lab? Did you complete at least 3 GOOD trials? The more the merrier! Homework: Lab Write Up Study for quiz Reminders: Parent Letter DUE – bring in ASAP Extra Credit Due Friday (5/11) Thermo Test Corrections Due Thursday (5/10) at 8:30 am Sig Figs Redemption Thursday (5/10) at 7:30 am Acid/Base Quiz Friday (5/11)