A chemist titrates 210.0 mL of a 0.5926M dimethylamine ((CH3)2NH) solution with 0.5782 M HBr solution at 25 °C. Calculate the pH at equivalence. The PK, of dimethylamine is 3.27. Round your answer to 2 decimal places. Note for advanced students: you may assume the total volume of the solution equals the initial volume plus the volume of HBr solution added. pH-0 =

Calculate the mass in grams of ammonium chloride, NH4C1, that would have to be added to 500. mL of 0.10-M NH3 solution to have a pH of 9.00.

A quantity of 0.25 M sodium hydroxide is added to a solution containing 0.15 mol of acetic acid. The final volume of the solution is 375 mL and the pH of this solution is 4.45. a What is the molar concentration of the sodium acetate? b How many milliliters of sodium hydroxide were added to the original solution? c What was the original concentration of the acetic acid?

A quantity of 0.15 M hydrochloric acid is added to a solution containing 0.10 mol of sodium acetate. Some of the sodium acetate is converted to acetic acid, resulting in a final volume of 650 mL of solution. The pH of the final solution is 4.56. a What is the molar concentration of the acetic acid? b How many milliliters of hydrochloric acid were added to the original solution? c What was the original concentration of the sodium acetate?

Two samples of 1.00 M HCl of equivalent volumes are prepared. One sample is titrated to the equivalence point with a 1.00 M solution of sodium hydroxide, while the other sample is titrated to the equivalence point with a 1.00 M solution of calcium hydroxide. a Compare the volumes of sodium hydroxide and calcium hydroxide required to reach the equivalence point for each titration. b Determine the pH of each solution halfway to the equivalence point. c Determine the pH of each solution at the equivalence point.

Water is accidentally added to 350.00 mL of a stock solution of 6.00 M HCI. A 75.00-mL sample of the diluted solution is titrated to pH 7.00 with 78.8 mL of 4.85 M NaOH. How much water was accidentally added? (Assume that volumes are additive.)

Methyl orange, HMO, is a common acid-base indicator. In solution it ionizes according to the equation: HMOaqH+aq+MO-aqredyellow If methyl orange is added to distilled water, the solution turns yellow. If 1 drop or two of 6 M HCl is added to the yellow solution, it turns red. If to that solution one adds a few drops of 6 M NaOH, the color reverts to yellow. a. Why does adding 6 M HCl to the yellow solution of methyl orange tend to cause the color to change to red? Note that in solution HCl exists as H+ and Cl- ions. b. Why does adding 6 M NaOH to the red solution tend to make it turn back to yellow? Note that in solution NaOH exists as Na+ and OH- ions. How does increasing OH- shift Reaction 3 in the discussion section? How would the resulting change in H+ affect the dissociation reaction of HMO?

A solution made up of 1.0 M NH3 and 0.50 M (NH4)2SO4 has a pH of 9.26. a Write the net ionic equation that represents the reaction of this solution with a strong acid. b Write the net ionic equation that represents the reaction of this solution with a strong base. c To 100. mL of this solution, 10.0 mL of 1.00 M HCl is added. How many moles of NH3 and NH4+ are present in the reaction system before and after the addition of the HCl? What is the pH of the resulting solution? d Why did the pH change only slightly upon the addition of HCl?

Sulfanilic acid (NH2C6H4SO3H) is used in manufacturing dyes. It ionizes in water according to the equilibrium equation NH2C6H4SO3H(aq)+H2O(l)NH2C6H4SO3(aq)+H3O+(aq)Ka=5.9104 A buffer is prepared by dissolving 0.20 mol of sulfanilicacid and 0.13 mol of sodium sulfanilate (NaNH2C6H4SO3) in water and diluting to 1.00 L. Compute the pH of the solution. Suppose 0.040 mol of HCl is added to the buffer.Calculate the pH of the solution that results.

Enough water is added to the buffer in Question 30 to make the total volume 5.00 L. (a) Calculate the pH of the buffer. (b) Calculate the pH of the buffer after adding 0.0250 mol of HCl to 0.376 L of the buffer. (c) Calculate the pH of the buffer after adding 0.0250 mol of KOH to 0.376 L of the buffer. (d) Compare your answers to Question 30 (a-c) with your answers to (a-c) of this problem. (e) Comment on the effect of dilution on the pH of a buffer and on its buffer capacity. Â