Three buffers are made by combining a 1M solution of acetic acid and a 1M solution of sodium acetate in the ratios shown in the table below. Which of these statements is true regarding the prepared buffers? (Ka= 1.7x10-5) 1M acetic acid 1M sodium acetate Buffer 1 10 ml 90 ml Buffer 2 50 ml 50 ml Buffer 3 90 ml 10 ml pH of buffer 1 > pH of buffer 2 = pH of buffer 3 pH of buffer 1 > pH of buffer 2 > pH of buffer 3 pH of buffer 1 < pH of buffer 2 < pH of buffer 3 pH of buffer 1 = pH of buffer 2 > pH of buffer 3 pH of buffer 1= pH of buffer 2 = pH of buffer 3

Three buffers are made by combining a 1M solution of acetic acid and a 1M solution of sodium acetate in the ratios shown in the table below. Which of these statements is true regarding the prepared buffers? (Ka= 1.7x10-5) 1M acetic acid 1M sodium acetate Buffer 1 10 ml 90 ml Buffer 2 50 ml 50 ml Buffer 3 90 ml 10 ml pH of buffer 1 > pH of buffer 2 = pH of buffer 3 pH of buffer 1 > pH of buffer 2 > pH of buffer 3 pH of buffer 1 < pH of buffer 2 < pH of buffer 3 pH of buffer 1 = pH of buffer 2 > pH of buffer 3 pH of buffer 1= pH of buffer 2 = pH of buffer 3

Chemistry: An Atoms First Approach

2nd Edition

ISBN:9781305079243

Author:Steven S. Zumdahl, Susan A. Zumdahl

Publisher:Steven S. Zumdahl, Susan A. Zumdahl

Chapter14: Acid- Base Equilibria

Section: Chapter Questions

Problem 102CWP: Consider the following acids and bases: HCO2H Ka = 1.8 104 HOBr Ka = 2.0 109 (C2H5)2NH Kb = 1.3 ...

See similar textbooks

Similar questions

Consider the following acids and bases: HCO2H Ka = 1.8 104 HOBr Ka = 2.0 109 (C2H5)2NH Kb = 1.3 103 HONH2 Kb = 1.1 108 Choose substances from the following list that would be the best choice to prepare a pH = 9.0 buffer solution. a. HCO2H b. HOBr c. KHCO2 d. HONH3NO3 e. (C2H5)2NH f. (C2H5)2NH2Cl g. HONH2 h. NaOBr
Each symbol in the box below represents a mole of a component in one liter of a buffer solution; represents the anion (X-), = the weak acid (HX), = H+, and =OH. Water molecules and the few H+ and OH- ions from the dissociation of HX and X- are not shown. The box contains 10 mol of a weak acid, , in a liter of solution. Show what happens upon (a) the addition of 2 mol of OH- (2 ). (b) the addition of 5 mol of OH- (5 ). (c) the addition of 10 mol of OH- (10 ). (d) the addition of 12 mol of OH- (12 ). Which addition (a)-(d) represents neutralization halfway to the equivalence point?
A chemist needs a buffer with pH 4.35. How many milliliters of pure acetic acid (density = 1.049 g/mL) must be added to 465 mL of 0.0941 M NaOH solution to obtain such a buffer?
What is the pH of a buffer that is 0.175 M in a weak acid and 0.200 M in the acids conjugate base? The acids ionization constant is 5.7 104.
A best buffer has about equal quantities of weak acid and conjugate base present as well as having a large concentration of each species present. Explain.
What mass of NH4Cl must be added to 0.750 L of a 0.100-M solution of NH3 to give a buffer solution with a pH of 9.26? (Him: Assume a negligible change in volume as the solid is added.)
Draw the general titration curve for a strong acid titrated by a strong base. At the various points in the titration, list the major species present before any reaction takes place and the major species present after any reaction takes place. What reaction takes place in a strong acidstrong base titration? How do you calculate the pH at the various points along the curve? What is the pH at the equivalence point for a strong acidstrong base titration? Why?
A sodium hydrogen carbonate-sodium carbonate buffer is to be prepared with a pH of 9.40. (a) What must the [ HCO3 ]/[ CO32 ]ratio be? (b) How many moles of sodium hydrogen carbonate must be added to a liter of 0.225 M Na2CO3 to give this pH? (c) How many grams of sodium carbonate must be added to 475 mL of 0.336 M NaHCO3 to give this pH? (Assume no volume change.) (d) What volume of 0.200 M NaHCO3 must be added to 735 mL of a 0.139 M solution of Na2CO3 to give this pH? (Assume that volumes are additive.)
A good buffer generally contains relatively equal concentrations of weak acid and conjugate base. If you wanted to buffer a solution at pH = 4.00 or pH = 10.00, how would you decide which weak acidconjugate base or weak baseconjugate acid pair to use? The second characteristic of a good buffer is good buffering capacity. What is the capacity of a buffer? How do the following buffers differ in capacity? How do they differ in pH? 0.01 M acetic acid/0.01 M sodium acetate 0.1 M acetic acid/0.1 M sodium acetate 1.0 M acetic acid/1.0 M sodium acetate
A chemist needs a buffer with pH 3.50. How many milliliters of pure formic acid (density = 1.220 g/mL) must be added to 375 mL of 0.0857 M NaOH solution to obtain such a buffer?
What is an acidbase indicator? Define the equivalence (stoichiometric) point and the end point of a titration. Why should you choose an indicator so that the two points coincide? Do the pH values of the two points have to be within 0.01 pH unit of each other? Explain.