Please show all your Solution/Calculations for the following problems. Box and express all your final answers in the correct significant figures and units accordingly.
I. Determining %Ionization as a Function of Weak Acid Concentration
1. What is the percent ionization of acetic acid in 1.0 M, 0.10 M and 0.010 M HC2H3O2? Ka = 1.8 x 10-5 [2pts]
2. What is the % ionization of hydrofluoric acid in (a) 0.20 M HF and (b) 0.020 M HF? Ka = 6.6 x 10-4 [4pts]
3. A 0.0284 M aqueous solution of lactic acid, HC3H5O3, a substance that accumulates in the blood and muscles during physical activity, is found to be 6.7% ionized. Determine Ka for lactic acid. [2pts]
II. The Common-Ion Effect in Acid-Base Equilibria
1. a) Determine [H3O+] and [F-] in 0.500 M HF. Ka HF = 6.6 x 10-4 b) Determine these concentrations in a solution that is 0.100 M HCl and 0.500 M HF. Ka HF = 6.6 x 10-4 [4pts]
2. Calculate [H3O+] and [COOH-] in a solution that is 0.100 M HCOOH, formic acid, and 0.150 M NaCOOH. Ka HCOOH = 1.8 x 10-4 [2pts]
III. Calculating the pH of a Buffer Solution
1. What is the pH of a buffer solution prepared by dissolving 25.5 g of NaC2H3O2 in a sufficient volume of 0.550 M HC2H3O2 to make 500.0 mL of the buffer? [2pts] Ka = 1.80 x 10-5
2. What is the pH of a buffer solution prepared by dissolving 23.1 g NaCHO2 in a sufficient volume of 0.432 M HCHO2 to make 500.0 mL of the buffer? Ka = 1.8 x 10-4 [2pts]
3. A handbook states that to prepare 100.0 mL of a particular buffer solution, mix 63.0 mL of 0.200 M HC2H3O2 with 37.0 mL of 0.200 M NaC2H3O2. Ka = 1.80 x 10-5. What is the pH of this buffer solution? [2pts]
IV. Practice: Calculating the Effect of Added H3O+ and OH- on Buffer pH
1. Calculate the pH of a buffer solution (a) consisting of 0.50 M HC2H3O2 and 0.50 M NaC2H3O2 Ka = 1.8 x 10-5 (b) after adding 0.020 mol HCl to 1.0 L of the buffer solution (c) after adding 0.020 mol NaOH to 1.0 L of the buffer solution [6pts]
2. Calculate the pH of a buffer consisting of 0.50 M HF and 0.45 M NaF. Ka = 6.8 x 10-4 a) Before b) After addition of 0.40 g NaOH to 1.0 L of the buffer [4pts]
Please show all your Solution/Calculations for the following problems. Box and express all your final answers in the cor
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