1. Acid and Base Ch 15 and 16 7-2

2. acids 1. tastes sour. 2. conducts an electric current. 3. Causes certain dyes ( indicators) to change color. 4. Liberates hydrogen when it reacts with certain metals. 5. neutralizes basic solutions to form salts.

3. Bases 1. tastes bitter. 2. conducts an electric current. 3. causes certain dyes ( indicators) to change color. 4. feels slippery. 5. neutralizes acid solution to form salts.

4. Definition of Acids and Bases An acid is a source of hydrogen ions (H + ) or hydronium ions (H 3 O + ) in solution. HCl(aq) + H 2 O(l) H 3 O + (aq) + Cl - (aq)

5. A base is a source of hydroxide ions (OH - ) e.g.NaOH(s) Na + (aq) + OH - (aq) e.g.NH 3 (aq) +H 2 O(l) NH 4 + (aq) + OH - (aq)

6. B. Definitions Arrhenius - In aqueous solution…Arrhenius - In aqueous solution… HCl + H 2 O H 3 O + + Cl – –Acids –Acids form hydronium ions (H 3 O + ) H HHHH H Cl OO – + acid

7. B. Definitions Arrhenius - In aqueous solution…Arrhenius - In aqueous solution… –Bases –Bases form hydroxide ions (OH - ) NH 3 + H 2 O NH 4 + + OH - H H H H H H N NO O – + H H H H base

8. B. Definitions Brønsted-LowryBrønsted-Lowry HCl + H 2 O  H 3 O + + Cl - –Acids –Acids are proton (H + ) donors. –Bases –Bases are proton (H + ) acceptors. conjugate base conjugate acid baseacid

9. Conjugate acid base pairs conjugate base: the species that remains after an acid has given up a proton conjugate acid: the species that is formed when a base gains a proton

10. NH 3 + H 2 O  NH 4 + + OH - conjugate base conjugate acid acid base

11. In the two examples water first acts as a base, then as an acid. Any species which can both accept and receive protons is called amphiprotic. (also known as amphoteric)

12. Br – HSO 4 - CO 3 2- HBr H 2 SO 4 HCO 3 - Give the conjugate acid for each of the following:

13. List the conjugate acids for the following Bronsted bases OH - CO 3 2- NO 3 - HCO 3 - CN - H2OH2O HCO 3 - HNO 3 HCO 3 HCN

14. F - H 2 PO 4 - H2OH2O HF H 3 PO 4 H 3 O + Give the conjugate base for each of the following: - an acid with more than one H +Polyprotic - an acid with more than one H +

15. List the conjugate bases for the following Bronsted acids H 2 SO 4 HPO 4 2- HCO 3 - H 3 O + H 2 PO 4 - HSO 4 - PO 4 3- CO 3 2- H2OH2O HPO 4 2-

16. Review 2: Name the acid, base, conjugate acid and base for each reaction. CH 3 NH 2 + H 2 O CH 3 NH 3 + + OH - H 3 PO 4 + H 2 O H 3 O + + H 2 PO 4 - HC 2 H 3 O 2 + H 2 O H 3 O + + C 2 H 3 O 2 - CH 3 NH 3 + + H 2 PO 4 - H 3 PO 4 + CH 3 NH 2 base acid conjugate acid conjugate base

17. Review 2: Name the acid, base, conjugate acid and base for each reaction. H 2 PO 4 - + OH - HPO 4 2- + H 2 O HCN + H 2 O CN - + H 3 O + NH 3 + H 2 O NH 4 + + OH - NO 2 - + HCO 3 - CO 3 2- + HNO 2 acid base acid base acid base conjugate base conjugate acid conjugate base conjugate acid conjugate base conjugate acid