Multiple Choice
Chemistry student is using an indicator with a pKa of 4.7 for the titration of a strong acid with strong base. Calculate the pH range at which the indicator will change colors.
a) 2.7–3.5 b) 10–11 c) 4.7–8.7 d) 3.7–5.7 e) 2.7–5.8
18. Aqueous Equilibrium
Acid-Base Indicators
Back18. Aqueous Equilibrium
Acid-Base Indicators
- Multiple Choice
Bromophenol blue (pKa = 4.1) is a common acid-base indicator. It is yellow in its acidic form and blue in conjugate base form. If the solution being titrated has a pH = 4.0, what color would the bromophenol blue indicator possess?
a) yellow b) orange c) blue d) green e) purple
- Open Question
When CO2 combines with water it forms carbonic acid. How does this explain the phenol red result?
- Open Question
A substance that changes color in the presence of an acid or base is called a(n)
- Multiple ChoiceWhat is the pH of the solution after titrating 25.00 mL of 0.22 M HC2H3O2 with 25.00 mL of 0.22 M NaOH?
- Multiple ChoiceA 60.0 mL solution of 0.115 M sodium hypochlorite (NaOCl) is titrated with 0.222 M NaOH. Calculate the pH of the solution after 6.05 mL of NaOH is added. The pKa of hypochlorous acid (HOCl) is 7.53.
- Multiple ChoiceWhat is the pH at the equivalence point for the titration of 20.0 mL of 0.500 M acetic acid (HC2H3O2) with 0.350 M potassium hydroxide (KOH), given that the Ka for acetic acid is 1.8 × 10^-5?
- Multiple ChoiceComplete neutralization of 12.5 mL of Sr(OH)₂ requires 36 mL of 0.1 M HCl. What is the concentration of the Sr(OH)₂ solution?
- Multiple ChoiceConsider the titration of 26.00 mL of 0.400 M formic acid with 0.380 M NaOH. Calculate the pH of the solution at the half-equivalence point.
- Multiple ChoiceDuring the titration of 26.00 mL of 0.400 M formic acid with 0.380 M NaOH, what is the pH of the solution at the half-equivalence point?
- Multiple ChoiceWhat is the pH of a solution after adding 4.3 mL of a strong acid beyond the equivalence point in a titration with a strong base?
- Multiple ChoiceWhich of the following indicators is most suitable for use in the titration of hypobromous acid (HBrO, pKa=8.7) with a strong base?
- Multiple ChoiceReferring to the table below, select an indicator for use in the titration of C6H5NH2 (pKb=9.41) with a strong acid. Which indicator would be most appropriate?
- Multiple ChoiceBased on the titration curves of a 1 M solution of a weak acid with a strong base and a 1 M solution of a strong acid with the same base, what is the estimated pKa of the weak acid?
- Multiple ChoiceGiven the following data: Volume of HA used = 9.19 mL, Volume of NaOH at equivalence point = 8.42 mL, pH at equivalence point = 8.66, and Concentration of NaOH = 0.1471 M, what is the pKa of the acid HA?