You are studying a clear solution and you added the pH indicator methyl violet. The colour range of the indicator methyl violet in a clear solution when changing from acidic to basic is yellow (pH 0) to blue purple (pH 1) to violet (pH 2). You initial pH of the solution when tested with a pH meter is O.2. You are going to add 250 drops of 0.1 M HCI. Please select the most appropriate answers to the following two questions. What is the initial colour of the solution at pH 0.2? What is the colour of the solution and what will the pH be after the addition of the HCI? Select 2 correct answer(s) The colour of the solution after the addition of HCI will be clear and the pH will be less than O.2. OThe colour of the solution after the addition of HCI will be violet and the pH will be higher than 0.2.

You are studying a clear solution and you added the pH indicator methyl violet. The colour range of the indicator methyl violet in a clear solution when changing from acidic to basic is yellow (pH 0) to blue purple (pH 1) to violet (pH 2). You initial pH of the solution when tested with a pH meter is O.2. You are going to add 250 drops of 0.1 M HCI. Please select the most appropriate answers to the following two questions. What is the initial colour of the solution at pH 0.2? What is the colour of the solution and what will the pH be after the addition of the HCI? Select 2 correct answer(s) The colour of the solution after the addition of HCI will be clear and the pH will be less than O.2. OThe colour of the solution after the addition of HCI will be violet and the pH will be higher than 0.2.

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter14: Acids And Bases

Section: Chapter Questions

Problem 119QRT

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Similar questions

Amino acids are an important group of compounds. At low pH, both the carboxylic acid group (CO2H) and the amine group (NHR) are protonated. However, as the pH of the solution increases (say, by adding base), the carboxylic acid proton is removed, usually at a pH between 2 and 3. In a middle range of pHs, therefore, the amine group is protonated, but the carboxylic acid group has lost the proton. (This is called a zwitterion.) At more basic pH values, the amine proton is dissociated. What is the pH of a 0.20 M solution of alanine hydrochloride, [NH3CHCH3CO2H]Cl?
Write the chemical equation and the expression for the equilibrium constant, and calculate Kb for the reaction of each of the following ions as a base. (a) sulfate ion (b) citrate ion
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Consider all acid-base indicators discussed in this chapter. Which of these indicators would be suitable for the titration of each of these? (a) NaOH with HClO4 (b) acetic acid with KOH (c) NH3 solution with HBr (d) KOH with HNO3 Explain your choices.
Using the diagrams shown in Problem 10-117, which of the solutions would have the greatest buffer capacity, that is, greatest protection against pH change, when the following occurs? a. A strong acid is added to the solution. b. A strong base is added to the solution.
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You have a solution of the weak acid HA and add some of the salt NaA to it. What are the major species in the solution? What do you need to know to calculate the pH of the solution, and how would you use this information? How does the pH of the solution of just the HA compare with that of the final mixture? Explain.
Calculate the pH of each of the following solutions. (a) 10.0 mL of 0.300 M hydrofluoric acid plus 30.0 mL of 0.100 M sodium hydroxide (b) 100.0 mL of 0.250 M ammonia plus 50.0 mL of 0.100 M hydrochloric acid (c) 25.0 mL of 0.200 M sulfuric acid plus 50.0 mL of 0.400 M sodium hydroxide
For conjugate acidbase pairs, how are Ka and Kb related? Consider the reaction of acetic acid in water CH3CO2H(aq)+H2O(l)CH3CO2(aq)+H3O+(aq) where Ka = 1.8 105 a. Which two bases are competing for the proton? b. Which is the stronger base? c. In light of your answer to part b. why do we classify the acetate ion (CH3CO2) as a weak base? Use an appropriate reaction to justify your answer. In general, as base strength increases, conjugate acid strength decreases. Explain why the conjugate acid of the weak base NH3 is a weak acid. To summarize, the conjugate base of a weak acid is a weak base and the conjugate acid of a weak base is a weak acid (weak gives you weak). Assuming Ka for a monoprotic strong acid is 1 106, calculate Kb for the conjugate base of this strong acid. Why do conjugate bases of strong acids have no basic properties in water? List the conjugate bases of the six common strong acids. To tie it all together, some instructors have students think of Li+, K+, Rb+, Cs+, Ca2+, Sr2+, and Ba2+ as the conjugate acids of the strong bases LiOH, KOH. RbOH, CsOH, Ca(OH)2, Sr(OH)2, and Ba(OH)2. Although not technically correct, the conjugate acid strength of these cations is similar to the conjugate base strength of the strong acids. That is, these cations have no acidic properties in water; similarly, the conjugate bases of strong acids have no basic properties (strong gives you worthless). Fill in the blanks with the correct response. The conjugate base of a weak acid is a_____base. The conjugate acid of a weak base is a_____acid. The conjugate base of a strong acid is a_____base. The conjugate acid of a strong base is a_____ acid. (Hint: Weak gives you weak and strong gives you worthless.)