General Chemistry
Three unknown bases were titrated. At the equivalence point, base A had a pH of 3.67, base B had a pH of 6.91, and base C had a pH of 4.28. Identify the strongest base and the weakest base.
When 12.5 mL of 0.125 M weak base B is titrated with 0.125 M monoprotic strong acid HA, is the pH at the equivalence point less than, equal to, or greater than 7?
The image below shows the titration of a weak base with a strong acid.
Determine the volume of added acid where the equilibrium concentration of the species in the solution and Ka of the conjugate acid is used to calculate pH.
Three unknown acids were titrated against a strong base and the following pH values were noted when the equivalence points were reached:
Acid 1: 7.23
Acid 2: 9.12
Acid 3: 8.57
Which is the strongest and the weakest acid?
Identify the acid-base mixture with the greater pH value.
Is the pH of the solution at the equivalence point acidic, neutral, or basic for the following acid-base titration?
Formic acid (HCOOH) and KOH
(C2H5)2NH and HCl
Various stages of the titration of a weak base, NH3, with a strong acid, HBr, are depicted by the following set of four diagrams. Br– ions and water molecules have been excluded for simplicity.
What is the pH of the solution at the equivalence point?
HNO3 is a strong acid. When an equal molar amount of KOH is added to an HNO3 solution, an acid-base reaction takes place. Which of the following figures depicts the reaction mixture when the system reaches equilibrium? Note that K+ ions have been omitted for clarity.
A 50.0 mL aqueous solution contains hydrobromic acid (HBr) and citric acid (C6H8O7) and was titrated against a 0.15 M aqueous solution of NaOH. The burette readings (volume of NaOH solution) for the first and second equivalence points were 74.8 mL and 87.5 mL, respectively. Determine the percentage of HBr that was neutralized at the first equivalence point.
Shown below are the titration curves of two acids each with a concentration of 0.050 M. A 40.00 mL sample of each acid was titrated with 0.05 M KOH.
Identify the titration curve that depicts a strong acid and the titration curve that depicts a weak acid.
Given equal volumes of each mixture component, determine which of the following is the most basic (highest pH).
Estimate the pKa of the weak acid.
A 0.2850 g sample of an unknown monoprotic acid was dissolved in 30.0 mL of water. The resulting solution was titrated with 0.115 M KOH solution. Calculate the molar mass of the acid if a total of 27.5 mL of KOH was used to reach the equivalence point.
The molar mass of an unknown monoprotic acid was determined by titrating it with a 0.0650 M KOH solution. A 0.2011 g sample of the acid required 25.3 mL of the KOH solution to reach the endpoint. What is the molar mass of the acid?
At the equivalence point, what is the pH of the titration of HNO3 with LiOH?
The samples of chloric acid and formic acid shown below are both titrated with 0.75 M KOH. Does chloric acid need more KOH to reach the equivalence point than formic acid?
Calculate the volume (in mL) of 0.125 M HBr required to titrate 34.5 mL of 0.135 M CH3NH2 to the equivalence point.
Consider a weak base (B) that can only accept one proton from an acid. A 0.15 M solution of a monoprotic strong acid (HA) was used to titrate 50.0 mL of a 0.20 M solution of B. Calculate the amount (in mol) of HA needed to reach the equivalence point.
If the same concentration of weak monoprotic acid and strong monoprotic acid is titrated with a strong base, will the strong monoprotic acid need more strong base than the weak acid to reach the equivalence point?
The images below show the different stages in the titration of a weak acid, HA, with KOH. Select the image that shows the titration curve after the addition of KOH but before the equivalence point. (K+ ions and water are not shown for clarity).
The samples of chloric acid and formic acid shown below are both titrated with 0.75 M KOH. Will their titration curves be identical after the equivalence point is reached?
The titration curve for two monoprotic acids is illustrated below. What is the pKa for the weak acid?
Potassium hydrogen phthalate (KHC8H4O4), abbreviated as KHP, is used for the standardization of bases used for titrations. The concentration of a lithium hydroxide solution was precisely determined by titrating 0.8585 g of KHP with the LiOH solution. A total of 19.63 mL of the LiOH solution was used to reach the equivalence point. Calculate the concentration of the LiOH solution.
Find the molar mass of the weak acid in the following scenario: A 2.50 mL solution of 3.00 M NaOH was mixed with a 6.51 g sample of a weak acid with Ka = 6.2x10-10. The resulting solution was diluted to 500.0 mL and was measured to have a pH of 7.72.
How much acid was added for the equivalence point to be reached? What is the pH at this point?
The images below show the titration curves of equal amounts of weak and strong monoprotic acid titrated with the same concentration of strong base.
Which of the following statements is true?
The images below show the individual titration curve of two weak acids, a and b, with a strong base
The images below show the individual titration curve of two weak bases, a and b, and a strong acid
0.127 M NaOH was used to titrate 0.219 g of an unknown monoprotic acid sample. Using the titration curve based on the gathered data, what are the pKa and molar mass of the acid?
a. Acid a has a larger Ka than acid b
b. Acid b has a larger Ka than acid a
c. Acid a and b have equal Ka
d. None of the above
Determine the volume of the added base where the pH is used for the calculations of equilibrium problems involving the Kb and concentration of the conjugate base based on the given curve for the titration of a weak monoprotic acid and a strong base
The equation for the reaction between nitrous acid and potassium hydroxide is
HNO2 + KOH → KNO2 + H2O
When 18.92 mL of HNO2 was titrated with 0.156 M KOH, 19.52 mL of KOH was required to reach the equivalence point. Calculate the mass of nitrous acid in grams present in a 1.00 qt sample
A 108.64 g sample of an unknown alkali metal hydroxide is dissolved in 150.0 mL of water. The solution is then titrated with 161 mL of 4.5 M HNO3 to reach the equivalence point. Calculate the molar mass of the metal hydroxide.
A 108.64 g sample of an unknown alkali metal hydroxide is dissolved in 150.0 mL of water. The solution is then titrated with 161 mL of 4.5 M HNO3 to reach the equivalence point. Identify the alkali metal.
Determine the molar mass of a 0.1093 g weak monoprotic acid that is neutralized by titration of 9.86 mL of 0.1787 M KOH.
A 2.591 g sample is dissolved in 50.00 mL of 1.045 M HCl solution. The solution needed 12.39 mL of 1.293 M KOH to neutralize the excess acid. If magnesium carbonate is the only compound that reacts with HCl, what is its percentage in the sample?
Which of the following curves shown below is closer to the actual data observed in a titration of acid using a strong base and phenolphthalein indicator?
The titration of a 30.00-mL sample of HClO4 solution with an unknown concentration required 22.50 mL of 0.3520 M NaOH to reach the equivalence point according to the following reaction:
HClO4(aq) + NaOH(aq) → H2O(l) + NaClO4(aq)
Calculate the concentration of the HClO4 solution.
2.25 g of a monoprotic weak acid sodium bicarbonate (MW = 84.0 g/mol) was dissolved into water to make a homogenous solution that was titrated against a 0.800 M solution of potassium hydroxide (KOH). Calculate the volume (in mL) of the KOH solution required to reach the equivalence point?
Identify the equivalence point pH for each of the following titrations:
1) Strong acid-strong base2) Strong acid-weak base3) Weak acid-strong base
The following titration curve was obtained when a 25.00 mL sample of HCl solution was titrated against 0.200 M NaOH solution. Calculate the morality of the HCl solution.
The following is a curve when a weak monoprotic acid is titrated against a strong base. Label the following titration events on the given titration curve:
A) The point where the pH of the solution is solely due to the presence of the weak acid.
B) The point where all of the weak acid has been neutralized by the strong base.
C) The region of the curve where there is a buffer solution present.
The titration curve shown below was obtained when a 10.0 mL sample of a weak base was titration against a 0.150 M HCl solution.
A. Calculate the initial molarity of the weak base solution.
B. What is the value of pKb for the weak base?
The titration curve shown below was obtained when a 20.0 mL sample of monoprotic acid was titrated against a solution of 0.15 M NaOH solution.
A. Calculate the initial concentration of the monoprotic acid in mol/L units.
B. Calculate the dissociation constant (Ka) for the monoprotic acid.
What is the pH after neutralization of the following acid and base pair: LiOH and HNO3?
One of the following graphs represents the titration of a strong base with a strong acid. Which titration curve is it?
