What is the pH at the equivalence point in the titration of a 28.6 mL sample of a 0.490 M aqueous hydrofluoric acid solution with a 0.466 M aqueous sodium hydroxide solution? pH =

A solution of sodium cyanide, NaCN, has a pH of 12.10. How many grams of NaCN are in 425 mL of a solution with the same pH?

Follow the directions of Question 64. Consider two beakers: Beaker A has a weak acid(K a=1105). Beaker B has HCI. The volume and molarity of each acid in the beakers are the same. Both acids are to be titrated with a 0.1 M solution of NaOH. (a) Before titration starts (at zero time), the pH of the solution in Beaker A is the pH of the solution in Beaker B. (b) At half-neutralization (halfway to the equivalence point), the pH of the solution in Beaker A the pH of the solution in Beaker B. (c) When each solution has reached its equivalence point, the pH of the solution in Beaker A the pH of the solution in Beaker B. (d) At the equivalence point, the volume of NaOH used to titrate HCI in Beaker B the volume of NaOH used to titrate the weak acid in Beaker A.

Assume you dissolve 0.235 g of the weak acid benzoic acid, C6H5CO2H, in enough water to make 1.00 102 mL of solution and then titrate the solution with 0.108 M NaOH. C6H5CO2H(aq) + OH(aq) C6H5CO2(aq) + H2O() (a) What was the pH of the original benzoic add solution? (b) What are the concentrations of all of the following ions at the equivalence point: Na+, H3O+, OH, and C6H5CO2? (c) What is the pH of the solution at the equivalence point?

Describe how the amount of sodium hydroxide in a mixture can be determined by titration with hydrochloric acid of known molarity.

A solution contains Ca2+ and Pb2+ ions, both at a concentration of 0.010 M. You wish to separate the two ions from each other as completely as possible by precipitating one but not the other using aqueous Na2SO4 as the precipitating agent. (a) Which will precipitate first as sodium sulfate is added, CaSO4 or PbSO4? (b) What will be the concentration of the first ion that precipitates (Ca2+ or Pb2+) when the second, more soluble salt begins to precipitate?

What acid-base indicators, shown in Figure 18.24 would be suitable for the neutralization reaction whose titration curve is shown in Figure 18.30?Why?

Rust, which you can take to be Fe(OH)3, can be dissolved by treating it with oxalic acid. An acid-base reaction occurs, and a complex ion is formed. (a) Write a balanced equation for the reaction. (b) What volume of 0.10 M H2C2O4 would be required to remove a rust stain weighing 1.0 g?

Consider the nanoscale-level representations for Question 110 of the titration of the aqueous weak acid HX with aqueous NaOH, the titrant. Water molecules and Na+ ions are omitted for clarity. Which diagram corresponds to the situation: After a very small volume of titrant has been added to the initial HX solution? When enough titrant has been added to take the solution just past the equivalence point? Halfway to the equivalence point? At the equivalence point? Nanoscale representations for Question 110.

A bottle of concentrated hydroiodic acid is 57% HI by weight and has a density of 1.70 g/mL. A solution of this strong and corrosive acid is made by adding exactly 10.0 mL to some water and diluting to 250.0 mL. If the information on the label is correct, what volume of 0.988 M NaOH is needed to neutralize the HI solution? Suggest an indicator for the titration.