Chapter 16, Problem 83CP

Write the net ionic equation in which the slightly soluble salt barium fluoride, BaF2, dissolves in dilute hydrochloric acid.

Many natural processes can be studied in the laboratory but only in an environment of controlled pH. Which of these combinations is the best to buffer the pH at approximately 7? Explain your choice. H3PO4/NaH2PO4 NaH2PO4/Na2HPO4 Na2HPO4/Na3PO4

Does the pH of the solution increase, decrease, or stay the same when you (a) Add solid sodium oxalate, Na2C2O4, to 50.0 mL of 0.015-M oxalic acid? (b) Add solid ammonium chloride to 100. mL of 0.016-M HCl? (c) Add 20.0 g NaCl to 1.0 L of 0.012-M sodium acetate, NaCH3COO?

A solution is prepared by dissolving 0.350 g of benzoic acid, HC7H5O2, in water to make 100.0 mL of solution. A 30.00-mL sample of the solution is titrated with 0.272 M KOH. Calculate the pH of the solution (a) before titration. (b) halfway to the equivalence point. (c) at the equivalence point.

Phenol, C6H5OH, is a weak organic acid. Suppose 0.515 g of the compound is dissolved in enough water to make 125 mL of solution. The resulting solution is titrated with 0.123 M NaOH. C6H5OH(aq) + OH(aq) C6H5O(aq) + H2O() (a) What is the pH of the original solution of phenol? (b) What are the concentrations of all of the following ions at the equivalence point: Na+, H3O+, OH, and C6H5O? (c) What is the pH of the solution at the equivalence point?

A buffer is made by adding 0.68 g of sodium formate, NaHCOO (molar mass = 68.0 g/mol), to 1.00 L of 0.015 M formic acid, HCOOH (K a = 1.8 × 10−4). The pH of the buffer is 3.57. What will the pH be after 10.0 mL of 0.50 M HCl(aq) is added to the buffer? I know how to solve it, I just don't know what the equation of the buffer is supposed to look like. I have HCOO- <---> HCl + HCOOH, but I don't think that's right. Thank you!

A student was required to prepare 250.0 mL of a cyanoacetic acid/sodium cyanoacetate buffer in which the concentration of the weak acid component was 0.06 M and the concentration of the conjugate base was 0.028 M. The student was supplied with 0.512 M cyanoacetic acid and 1.0M NaOH to perform this task. What volume (in mL) of the acid would the student need to prepare this buffer solution? Hint: assume that all of the conjugate base comes directly from the reaction of NaOH with the weak acid (in other words, there is negligible dissociation of the weak acid). Please enter answers with 2 decimal places.

31. (a) Calculate the pH of a mixture containing 0.1 M propanoic acid (CH3CH₂COOH) and 0.050 M sodium propanoate (CH3CH₂COONa) (b) Determine the change in pH that occurs when 0.15 mol solid NaOH is added to 1.00 litre of the buffered solution. 32. (a) Calculate the pH of a buffer solution produced by adding 3.28 g of sodium ethanoate to 1 dm3 of 0.01 M of ethanoic acid (Ka = 1.84x 10-5 at 300K) (b) calculate the pH of this buffer if 10 cm3 of 0.1 M HCl are now added

A chemistry graduate student is given 300. mL of a 1.60M pyridine (C H,N) solution. Pyridine is a weak base with K,=1.7 × 10 What mass of CH,NHC1 should the student dissolve in the CH,N solution to turn it into a buffer with pH = 5.16? You may assume that the volume of the solution doesn't change when the CH,NHCI is dissolved in it. Be sure your answer has a unit symbol, and round it to 2 significant digits.