Answers: (1) acidic, basic, or neutral? 1.5x10-2 M x10-13 M acidic

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1 Acids and Bases Name: (1) Complete the following table. [H ph poh [OH acidic, basic, or neutral? 1.5x10 M x10 8 M neutral () Classify the following substances as acidic or basic and determine the [H and [OH. (a) Draino, ph 1.50 (c) Lye poh.60 (b) Vinegar ph.40 (d) Cola poh () Determine the ph and poh of the following solutions. (a) M HBr (c) 5.6x10 M LiOH (b) 1.x10 4 M HNO (d) 0.00 M Sr(OH) Answers: (1) [H ph poh [OH acidic, basic, or neutral? 1.5x10 M x10 1 M acidic 5.8x10 9 M x10 6 M basic 6.0x10 1 M x10 M basic.6x10 7 M x10 8 M acidic 1.0 x10 7 M x10 7 M neutral () (a) basic [H.x10 1 M [OH.1x10 M (b) acidic [H 4.0x10 M [OH.5x10 1 M (c) basic [H 4.0x10 1 M [OH.5x10 M (d) acidic [H.1x10 4 M [OH.x10 11 M () (a) ph 1.40 poh 1.60 (b) ph.9 poh (c) ph poh.5 (d) ph 1.60 poh 1.40

2 BronstedLowry Acids and Bases Name: (1) Write the formula for the conjugate base of the following acids. (a) HOCl (e) H BO (b) HNO (f) H PO 4 (c) H SO (g) HSO 4 (d) H CO (h) HC O 4 () Write the formula for the conjugate acid of the following bases. (a) NH (e) H PO 4 (b) C 6 H 5 NH (f) SO (c) CN (g) CO (d) OBr (h) BO () Write a K a or K b expression for the following acid or base equilibria. Identify the conjugate acidbase pairs. (a) HCN (aq) H O (l) H O (aq) CN (aq) (b) C H 5 NH (aq) H O (l) OH (aq) C H 5 NH (aq) (c) OCl (aq) H O (l) OH (aq) HOCl (aq) (d) HSO (aq) H O (l) H O (aq) SO (aq) (4) Complete the following acid or base equilibria. Identify the conjugate acidbase pairs and write a K a or K b expression. (a) HIO (aq) H O (l) (d) HONH (aq) H O (l) (b) C 5 H 5 N (aq) H O (l) (e) [Cr(H O) 6 (aq) H O (l) (c) H C O 4 (aq) H O (l). (5) Calculate the ph and poh for the following solutions. (a) 0.10 M HC H O (b) 0.40 M NH (c) 0.06 HCN (d) 0.4 M HONH (6) The ph of 0.50 M solution of Ascorbic Acid (HC 6 H 7 O 6 ) is.5. Determine K a. (7) The poh of a 0.40 M solution of Ephedrine (C 10 H 15 ON) is.16. Determine K b. (8) Determine the percent dissociation for the following compounds. (a) 0.14 M HOCl (b) 0.5 M C H 5 NH (9) The percent dissociation for a M solution of Morphine (C 17 H 19 N) is 0.7%. Determine K b. (10) The percent dissociation for a 0.00 M solution of formic acid (HCO H) is.0%. Determine K a.

3 Answers: (1) (a) OCl (b) NO (c) HSO (d) HCO (e) H BO (f) HPO 4 (g) SO 4 (h) C O 4 () (a) NH 4 (b) C 6 H 5 NH (c) HCN (d) HOBr (e) H PO 4 (f) HSO (g) HCO (h) HBO () (a) HCN (aq) H O (l) H O (aq) CN (aq) (c) OCl (aq) H O (l) OH (aq) HOCl (aq) b a cb ca [ CN [ OH Cl Kb [ HCN [ OCl (b) C H 5 NH (aq) H O (l) OH (aq) C H 5 NH (aq) b a cb ca [ OH [ CH5NH Kb [ CHNH 5 (d) HSO (aq) H O (l) H O (aq) SO (aq) [ SO [ HSO (4) (a) HIO (aq) H O (l) H O (aq) IO (aq) [ IO [ HIO (b) C 5 H 5 N (aq) H O (l) OH (aq) C 5 H 5 NH (aq) b a cb ca [ OH [C5H5NH Kb [C H N 5 5 (c) H C O 4 (aq) H O (l) H O (aq) HC O 4 (aq) [ HCO 4 [ HCO 4 (d) HONH (aq) H O (l) OH (aq) HONH (aq) b a cb ca [ OH [HONH Kb [HONH (e) [Cr(H O) 6 (aq) H O (l) H O (aq) [Cr(H O) 5 (OH) (aq) [[ CrHO ( ) 5( OH) [[ Cr( H O) 6 (5) (a) ph.89 poh (b) ph 11.4 poh.57 (c) ph 5. poh 8.67 (d) ph 9.8 poh 4.17 (6) K a 8.x10 5 (7) K b 1.4x10 4 (8) (a) 0.050% (b) 4.8% (9) K b 8.1x10 7 (10) K a 1.9x10 4

4 Acid Base Equilibria Name: (1) Determine the K b value for the following bases. (a) F (b) OCl (c) HSO () Determine the K a value for the following acids. (a) HONH (b) C H 5 NH (c) CH NH () (a) Rank the following substances from the strongest to weakest acid: HIO, HF, HClO, HCN. Explain. (b) Rank the following substances from the strongest to weakest base: IO, F, ClO, CN. Explain (4) (a) Rank the following substances from strongest to weakest base: N H 4, C H5NH, C 5 H 5 N, HONH. Explain (b) Rank the following substances from the strongest to weakest acid: NH 5, C H 5 NH, C 5 H 5 NH, HONH. Exlain. (5) Complete the following acidbase equilibria. Calculate an equilibrium constant for the reaction. Does the equilibrium favour the reactants or products? Which is the stronger acid in the equilibrium? Which is the stronger base in the equilibrium? (a) CH NH (aq) HOBr (aq) (b) HONH (aq) HOCl (aq) (6) Determine an equilibrium constant for the following reaction: H S (aq) H O (l) H O (aq) S (aq) H S (aq) H O (l) H O (aq) HS (aq) K a1 HS (aq) H O (l) H O (aq) S (aq) K a (7) A solution contains HSO. Write two equations to show that this compound is amphoteric and determine an equilibrium constant for each. Would the solution be acidic or basic? (8) Calculate the ph and poh of a solution containing 0.10 M HBr and 0.10 M HOBr (9) Calculate the ph and poh of a solution containing M LiOH and M N H 4. (10) Calculate the ph and poh of a mixture containing 0.0 M HNO and 0.0 M HOCl. (11) Calculate the ph and poh of a mixture containing 0.15 M CH NH and 0.15 M C 6 H 5 NH. (1) Calculate the ph and poh of a solution containing 0.50 M HNO and 0.50 M NaNO (1) Calculate the ph and poh of a solution containing 1.0 M CH NH and 1.0 M CH NH Cl (14) Determine if the following salts will be acidic, basic, or neutral. Explain. (a) LiCl (e) NH 4 IO 4 (b) KCN (f) C 5 H 5 NHClO (c) NH 4 ClO (g) C H 5 NH NO (d) CsNO (h) BaBr (15) Calculate the ph and poh of the following salts. (a) 0. M NaOCl (b) M CH NH I (c) 0.06 M LiF (d) M HONH Br (e) 0.50 M NH 4 OCl (f) 0.40 M C 5 H 5 NHOBr

5 Answers: (1) (a) K b 1.4x10 11 (b) K b.9x10 7 (c) K b 6.7x10 1 () (a) K a 9.1x10 7 (b) K a 1.8x10 11 (c) K a.x10 11 () (a) HIO > HClO > HF > HCN The larger the K a, the stronger the acid. (b) CN > F > ClO > IO The stronger the acid, the weaker the conjugate base; the weaker the acid, the stronger the conjugate base. (4) (a) C H 5 NH > N H 4 > HONH > C 5 H 5 N The larger the K b, the stronger the base. (b) C 5 H 5 NH > HONH > N H 5 > C H 5 NH The stronger the base, the weaker the conjugate acid; the weaker the base, the stronger the conjugate acid. (5) (a) K 88 Since K>1, the equilibrium favours the products. HOBr is a stronger acid than CH NH, and CH NH is a stronger base than OBr. (b) K 0.09 Since K<1, the equilibrium favours the reactants. HONH is a stronger acid than HOCl, and OCl is a stronger base than HONH. (6) K 1.x10 0 (7) acid: HSO (aq) H O (l) H O (aq) SO (aq) K a 1.0x10 7 base: HSO (aq) H O (l) OH (aq) H SO (aq) K b 6.7x10 1 The solution would be acidic since K a > K b. (8) ph 1.00 and poh 1.00 (9) ph 1,70 and poh 1.0 (10) ph.05 and poh (11) ph and poh.09 (1) ph.40 poh (1) ph poh.6 (14) (a) neutral (b) basic (c) acidic (d) basic (e) acidic (f) acidic (K a >K b ) (g) basic (K b >K a ) (h) neutral (15) (a) ph poh.60 (b) ph 6. poh 7.77 (c) ph 7.97 poh 6.0 (d) ph.89 poh (e) ph poh.44 (f) ph 4.00 poh 10.00

6 Name: Buffers (1) Calculate the ph and poh of the following buffer solutions. (a) 0.40 M HNO and 0.40 M NaNO (b) 0.5 M NH and 0.5 M NH 4 I () (a) Calculate the ph resulting from adding mol of KOH to 1.0 L of the buffer in 1a. (b) Calculate the ph resulting from adding mol of HCl to 100 ml of the buffer in 1a. (c) Calculate the ph resulting from adding 0.00 mol of NaOH to 500 ml of the buffer in 1a. (d) Calculate the ph resulting from adding mol of HBr to 800 ml of the buffer in 1a. () (a) Calculate ph resulting from adding mol of HBr to 1.0 L of the buffer in 1b. (b) Calculate the ph resulting from adding mol of NaOH to 100 ml of the buffer in 1b. (c) Calculate ph resulting from adding mol of HCl to 600 ml of the buffer in 1b. (d) Calculate the ph resulting from adding 0.00 mol of LiOH to 500 ml of the buffer in 1b. (4) (a) Determine the ph and poh of a buffer prepared by adding 0.50 g of sodium fluoride (NaF) to 400 ml of M hydrofluoric acid (HF). Assume the volume of the solution remains constant. (b) Determine the ph and poh of a buffer prepared by adding 4.85 g of hydrazinium chloride (N H 5 Cl) to 600 ml of 0.4 M hydrazine (N H 4 ). Assume the volume of the solution remains constant. (5) Determine the mass of sodium acetate (NaC H O ) that must be added to 750 ml of 0.0 M acetic acid (HC H O ) in order to make a buffer with ph 4.6. Assume the volume of the solution remains constant (6) Determine the mass of triethylammonium chloride (C 6 H 15 NHCl) that must be added to 1.0 L of 0.40 M triethylamine (C 6 H 14 N) in order to make a buffer with ph Assume the volume of the solution remains constant Answers: (1) (a) ph.40 poh (b) poh 4.74 ph 9.6 () (a) ph.4 (b) ph.9 (c) ph.49 (d) ph.6 () (a) ph 9. (b) ph 9. (c) ph 9.1 (d) ph 9.40 (4) (a) ph.5 poh (b) poh 5.1 ph 8.79 (5) 9. g NaC H O (6) 70 g C 6 H 15 NHCl

7 Titrations Name: (1) Give the net ionic equations the following neutralization reactions. (a) LiOH HCl (d) HF RbOH (b) HNO KOH (c) NH HBr (e) Ba(OH) HI (f) H SO 4 CsOH () What volume of M NaOH is required to titrate ml of 0.5 M HC H O? () What is the concentration if ml of NH requires ml of M HCl to titrate? (4) Strong Base/Strong Acid A M solution of HCl is used to titrate ml of a M NaOH solution. Determine the ph at the following intervals in the experiment. Graph the results. Label the equivalence point. (1) No HCl has been added ph (5) ml of HCl has been added ph () 5.00 ml of HCl has been added ph (6) 15.0 ml of HCl has been added ph () ml of HCl has been added ph (7) ml of HCl has been added ph (4) ml of HCl has been added ph (8) ml of HCl has been added ph 1.85 (9) 00.0 ml of HCl has been added. ph 1.77 Strong Acid Strong Base Titration ph Volume HCl added (ml)

8 (5) Strong Base/Weak Acid A M solution of NaOH is used to titrate ml of a M HC H O solution. Determine the ph at the following intervals in the experiment. Graph the results. Label the equivalence point. (1) No NaOH has been added ph (5) ml of NaOH has been added ph () 5.00 ml of NaOH has been added ph (6) 15.0 ml of NaOH has been added ph () ml of NaOH has been added ph 4.74 (7) ml of NaOH has been added ph 1.0 (4) ml of NaOH has been added ph (8) ml of NaOH has been added ph (9) 00.0 ml of NaOH has been added. ph 1.5 Weak Acid Strong Base Titration ph Volume NaOH added (ml) Answers: (1) (a) OH H H O (d) HF OH F H O (b) HNO OH NO H O (c) NH H NH 4 (e) OH H H O (f) H HSO 4 OH SO 4 H O () 0.5 L NaOH () M NH (4) (1) ph 1.70 () ph 1.48 () ph 1. (5) ph 7.00 (equivalence point) (6) ph.5 (7) ph.00 (5) (1) ph.87 () ph 4.7 (4) ph 5. (5) ph 8.7 (equivalence point) (6) ph 1.04 (8) ph 1.4