on 4. A weak acid (HA) has a pKa of 5. Suppose you have 120 mL of a HA and its conjugate base A- at pH 5.6. (Note: not 1M of each, but a total concentration of 1M of both acid and conjugate base together). To this 1M buffer solution, is added 10 mL of 1.0 M HCL. What is the pH of the resulting solution? What would be the pH of the solution if 10mL of 1M HCL were added to 120ml pure water without the presence of the buffer?

on 4. A weak acid (HA) has a pKa of 5. Suppose you have 120 mL of a HA and its conjugate base A- at pH 5.6. (Note: not 1M of each, but a total concentration of 1M of both acid and conjugate base together). To this 1M buffer solution, is added 10 mL of 1.0 M HCL. What is the pH of the resulting solution? What would be the pH of the solution if 10mL of 1M HCL were added to 120ml pure water without the presence of the buffer?

Chemistry: Principles and Reactions

8th Edition

ISBN:9781305079373

Author:William L. Masterton, Cecile N. Hurley

Publisher:William L. Masterton, Cecile N. Hurley

Chapter14: Equilibria In Acid-base Solutions

Section: Chapter Questions

Problem 33QAP: A buffer is prepared in which the ratio [ H2PO4 ]/[ HPO42 ]is 3.0. (a) What is the pH of this...

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Similar questions

A friend asks the following: Consider a buffered solution made up of the weak acid HA and its salt NaA. If a strong base like NaOH is added, the HA reacts with the OH to form A. Thus the amount of acid (HA) is decreased, and the amount of base (A) is increased. Analogously, adding HCI to the buffered solution forms more of the acid (HA) by reacting with the base (A). Thus how can we claim that a buffered solution resists changes in the pH of the solution? How would you explain buffering to this friend?
The species called glacial acetic acid is 98% acetic acid by mass (d=1.0542g/mL). What volume of glacial acetic acid must be added to 100.0 mL of 1.25 M NaOH to give a buffer with a pH of 4.20?
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.)
How many grams of HI should be added to 265 mL of 0.215 M HCI so that the resulting solution has a pH of 0.38? Assume that the addition of HI does not change the volume of the resulting solution.
A quantity of 0.25 M sodium hydroxide is added to a solution containing 0.15 mol of acetic acid. The final volume of the solution is 375 mL and the pH of this solution is 4.45. a What is the molar concentration of the sodium acetate? b How many milliliters of sodium hydroxide were added to the original solution? c What was the original concentration of the acetic acid?
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?
. Which component of a buffered solution is capable of combining with an added strong acid? Using your example from Exercise 60, show how this component would react with added HC1.
You have 0.10-mol samples of three acids identified simply as HX, HY, and HZ. For each acid, you make up 0.10 M solutions by adding sufficient water to each of the acid samples. When you measure the pH of these samples, you find that the pH of HX is greater than the pH of HY, which in turn is greater than the pH of HZ. a Which of the acids is the least ionized in its solution? b Which acid has the largest Kd?