Chemistry: The Molecular Science
5th Edition
ISBN: 9781285199047
Author: John W. Moore, Conrad L. Stanitski
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 15, Problem 85QRT
A buffer solution was prepared by adding 4.95 g sodium acetate to 250. mL of 0.150-M acetic acid.
- (a) What ions and molecules are present in the solution? List them in order of decreasing concentration.
- (b) Calculate the pH of the buffer solution.
- (c) Calculate the pH of 100. mL of the buffer solution if you add 80. mg NaOH. (Assume negligible change in volume.)
- (d) Write a net ionic equation for the reaction that occurs to change the pH.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
(a) A 50.0 mL solution is prepared to be 1.29 M acetylsalicylic acid. In the first step, 8.55 mL of NaOH is titrated into the solution until the pH is exactly 5.0. What is the concentration of the titrant (NaOH)?
(b) In the second step, enough 5.85 M nitric acid is added to the solution after the titration in part (a) is complete until the pH is one unit lower than the pKa of acetylsalicylic acid. What volume (mL) of nitric acid was added?
A buffer solution was made by mixing 2.00 L of 1.500 M potassium nitrite with 1.00 L of 1.476 M nitrous acid.
Ka (nitrous acid) = 4.5 x 10-4
For all to the following questions, write your answer as a normal number to three significant figures.
(a) The molarity of the conjugate base in the solution at the instant of mixing is
(b) The molarity of the weak acid in the solution at the instant of mixing is
(c) The pH of the buffer after the mixing of the two solutions is
Use the rules applicable to significant figures.
(d) 19.04 g NaOH (39.9971 g/mol) is dissolved in this buffer solution (assume this causes no change in the volume of the solution) and reacts. The mole of
added base remaining after the reaction is
(e) At the same time, the moles of weak acid remaining is
(f) At the same time, the moles of the conjugate base remaining is
(9) THe pH of the buffer solution after the added base has reacted, is
Use the rules applicable to significant figures.
4. How does the pH of each of the following solutions change when 5.0 mL of 1.0 M NaOH (a
strong base) is added? Fill in the table. Give your answers with 2 decimals.
Initial pH
Final pH after adding NaOH
Solution
(a) 100.0 ml water
(b)
(c)
100.0 mL 0.150 M HNO2 (a weak acid)
(Given: Ka = 4.5 × 10-4)
100.0 mL solution of 0.150 M HNO2 and
0.100 M NaNO₂
Chapter 15 Solutions
Chemistry: The Molecular Science
Ch. 15.1 - Predict whether 1.0 L of each solution is a...Ch. 15.1 - Calculate the pH of blood containing 0.0020-M...Ch. 15.1 - Prob. 15.2ECh. 15.1 -
Calculate the ratio of [] to [] in blood at a...Ch. 15.1 - Use the data in Table 15.1 to select a conjugate...Ch. 15.1 -
Calculate the mole ratio of sodium acetate and...Ch. 15.1 - Calculate the pH of these buffers.
Ch. 15.1 - If an abnormally high CO2 concentration is present...Ch. 15.1 - Calculate the minimum mass (g) of KOH that would...Ch. 15.2 - For the titration of 50.0 mL of 0.100-M HCl with...
Ch. 15.2 - Draw the titration curve for the titration of 50.0...Ch. 15.2 - Use the Ka expression and value for acetic acid to...Ch. 15.2 - Explain why the curve for the titration of acetic...Ch. 15.4 - Write the Ksp expression for each of these...Ch. 15.4 - The Ksp of AgBr at 100 C is 5 1010. Calculate the...Ch. 15.4 - A saturated solution of silver oxalate. Ag2C2O4....Ch. 15.4 - Prob. 15.9CECh. 15.5 - Consider 0.0010-M solutions of these sparingly...Ch. 15.5 - Prob. 15.11PSPCh. 15.5 - Calculate the solubility of PbCl2 in (a) pure...Ch. 15.5 - Prob. 15.13PSPCh. 15.6 - (a) Determine whether AgCl precipitates from a...Ch. 15.6 - Prob. 15.15PSPCh. 15 - Prob. 1SPCh. 15 - Choose a weak-acid/weak-base conjugate pair from...Ch. 15 - Prob. 4SPCh. 15 - Define the term buffer capacity.Ch. 15 - What is the difference between the end point and...Ch. 15 - What are the characteristics of a good acid-base...Ch. 15 - A strong acid is titrated with a strong base, such...Ch. 15 - Repeat the description for Question 4, but use a...Ch. 15 - Use Le Chatelier’s principle to explain why PbCl2...Ch. 15 - Describe what a complex ion is and give an...Ch. 15 - Define the term “amphoteric”.
Ch. 15 - Distinguish between the ion product (Q) expression...Ch. 15 - Describe at least two ways that the solubility of...Ch. 15 - Briefly describe how a buffer solution can control...Ch. 15 - Identify each pair that could form a buffer. (a)...Ch. 15 - Identify each pair that could form a buffer. (a)...Ch. 15 - Many natural processes can be studied in the...Ch. 15 - Which of these combinations is the best to buffer...Ch. 15 - Without doing calculations, determine the pH of a...Ch. 15 - Without doing calculations, determine the pH of a...Ch. 15 - Select from Table 15.1 a conjugate acid-base pair...Ch. 15 - Select from Table 15.1 a conjugate acid-base pair...Ch. 15 - Calculate the mass of sodium acetate, NaCH3COO,...Ch. 15 - Calculate the mass in grams of ammonium chloride,...Ch. 15 - A buffer solution can be made from benzoic acid,...Ch. 15 - A buffer solution is prepared from 5.15 g NH4NO3...Ch. 15 - You dissolve 0.425 g NaOH in 2.00 L of a solution...Ch. 15 - A buffer solution is prepared by adding 0.125 mol...Ch. 15 - If added to 1 L of 0.20-M acetic acid, CH3COOH,...Ch. 15 - If added to 1 L of 0.20-M NaOH, which of these...Ch. 15 - Calculate the pH change when 10.0 mL of 0.100-M...Ch. 15 - Prob. 29QRTCh. 15 - Prob. 30QRTCh. 15 - Prob. 31QRTCh. 15 - The titration curves for two acids with the same...Ch. 15 - Explain why it is that the weaker the acid being...Ch. 15 - Prob. 34QRTCh. 15 - Consider all acid-base indicators discussed in...Ch. 15 - Which of the acid-base indicators discussed in...Ch. 15 - It required 22.6 mL of 0.0140-M Ba(OH)2 solution...Ch. 15 - It took 12.4 mL of 0.205-M H2SO4 solution to...Ch. 15 - Vitamin C is a monoprotic acid. To analyze a...Ch. 15 - An acid-base titration was used to find the...Ch. 15 - Calculate the volume of 0.150-M HCl required to...Ch. 15 - Calculate the volume of 0.225-M NaOH required to...Ch. 15 - Prob. 43QRTCh. 15 - Prob. 44QRTCh. 15 - Prob. 45QRTCh. 15 - Explain why rain with a pH of 6.7 is not...Ch. 15 - Identify two oxides that are key producers of acid...Ch. 15 - Prob. 48QRTCh. 15 - Prob. 49QRTCh. 15 - Prob. 50QRTCh. 15 - Prob. 51QRTCh. 15 - A saturated solution of silver arsenate, Ag3AsO4,...Ch. 15 - Prob. 53QRTCh. 15 - Prob. 54QRTCh. 15 - Prob. 55QRTCh. 15 - Prob. 56QRTCh. 15 - Prob. 57QRTCh. 15 - Prob. 58QRTCh. 15 - Prob. 59QRTCh. 15 - Prob. 60QRTCh. 15 - Prob. 61QRTCh. 15 - Prob. 62QRTCh. 15 - Prob. 63QRTCh. 15 - Prob. 64QRTCh. 15 - Predict what effect each would have on this...Ch. 15 - Prob. 66QRTCh. 15 - Prob. 67QRTCh. 15 - The solubility of Mg(OH)2 in water is...Ch. 15 - Prob. 69QRTCh. 15 - Prob. 70QRTCh. 15 - Prob. 71QRTCh. 15 - Prob. 72QRTCh. 15 - Write the chemical equation for the formation of...Ch. 15 - Prob. 74QRTCh. 15 - Prob. 75QRTCh. 15 - Prob. 76QRTCh. 15 - Prob. 77QRTCh. 15 - Prob. 78QRTCh. 15 - Prob. 79QRTCh. 15 - Prob. 80QRTCh. 15 - Prob. 81QRTCh. 15 - Solid sodium fluoride is slowly added to an...Ch. 15 - Prob. 83QRTCh. 15 - Prob. 84QRTCh. 15 - A buffer solution was prepared by adding 4.95 g...Ch. 15 - Prob. 86QRTCh. 15 - Prob. 87QRTCh. 15 - Prob. 88QRTCh. 15 - Prob. 89QRTCh. 15 - Which of these buffers involving a weak acid HA...Ch. 15 - Prob. 91QRTCh. 15 - Prob. 92QRTCh. 15 - When 40.00 mL of a weak monoprotic acid solution...Ch. 15 - Each of the solutions in the table has the same...Ch. 15 - Prob. 95QRTCh. 15 - Prob. 97QRTCh. 15 - The average normal concentration of Ca2+ in urine...Ch. 15 - Explain why even though an aqueous acetic acid...Ch. 15 - Prob. 100QRTCh. 15 - Prob. 101QRTCh. 15 - Prob. 102QRTCh. 15 - Prob. 103QRTCh. 15 - Prob. 104QRTCh. 15 - Apatite, Ca5(PO4)3OH, is the mineral in teeth.
On...Ch. 15 - Calculate the maximum concentration of Mg2+...Ch. 15 - Prob. 107QRTCh. 15 - Prob. 108QRTCh. 15 - The grid has six lettered boxes, each of which...Ch. 15 - Consider the nanoscale-level representations for...Ch. 15 - Consider the nanoscale-level representations for...Ch. 15 - Prob. 112QRTCh. 15 - Prob. 113QRTCh. 15 - Prob. 114QRTCh. 15 - Prob. 115QRTCh. 15 - You want to prepare a pH 4.50 buffer using sodium...Ch. 15 - Prob. 117QRTCh. 15 - Prob. 118QRTCh. 15 - Prob. 119QRTCh. 15 - Prob. 120QRTCh. 15 - Prob. 121QRTCh. 15 - Prob. 122QRTCh. 15 - You are given four different aqueous solutions and...Ch. 15 - Prob. 124QRTCh. 15 - Prob. 126QRTCh. 15 - Prob. 15.ACPCh. 15 - Prob. 15.BCP
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- One half liter (500. mL) of 2.50 M HCl is mixed with 250. mL of 3.75 M HCl. Assuming the total solution volume after mixing is 750. mL, what is the concentration of hydrochloric acid in the resulting solution? What is its pH?arrow_forwardA scientist has synthesized a diprotic organic acid, H2A, with a molar mass of 124.0 g/mol. The acid must be neutralized (forming the potassium salt) for an important experiment. Calculate the volume of 0.221 M KOH that is needed to neutralize 24.93 g of the acid, forming K2A.arrow_forwardAn acid is titrated with NaOH. The following beakers are illustrations of the contents of the beaker at various times during the titration. These are presented out of order. Note: Counter-ions and water molecules have been omitted from the illustrations for clarity. (a) (b) (c) (d) (e) a. Is the acid a weak or strong acid? How can you tell? b. Arrange the beakers in order of what the contents would look like as the titration progresses. c. For which beaker would pH = pKa? Explain your answer. d. Which beaker represents the equivalence point of the titration? Explain your answer. e. For which beaker would the Ka value for the acid not be necessary to determine the pH? Explain your answer.arrow_forward
- A solution of hydrochloric acid has a volume of 250. mL and a pH of 1.92. Exactly 250. mL of 0.0105 M NaOH is added. What is the pH of the resulting solution?arrow_forward1) A drop of phenolphthalein is added to a solution of 1.0 M H2SO4 with a volume of 10.0 mL. The solution is mixed with 8.2 mL of 0.70 M NaOH. After the reaction is complete, is the solution acidic, basic, or neutral? What color is the indicator? Show all calculations and explain the answer with numbers. 2)) A 50.0 mL sample of H2SO4 is neutralized with a KOH solution having a concentration of 0.400 M. If 22.6 mL of KOH are required to complete the neutralization, what is the concentration of the sulfuric acid solution?arrow_forwardConsider an analyte solution of 50.0mL of 0.050M hydrochloric acid, HCl, titrated against 0.10 M sodium hydroxide, NaOH (the titration you will be performing in the lab!). (a) What is the chemical equation representing the titration reaction? (b) At the start of the titration, before any NaOH is added, what ions or molecules are present in the solution? You only need to list chemical species that are present in appreciable quantities - anything that is considered a small enough concentration to where you’d make a small-change approximation on an ICE table doesn’t need to be included. (c) Which of species you identified in part (b) will determine the pH of the solution? (d) After adding 12.50mL of the NaOH, halfway to the equivalence point, what ions or molecules are present in the solution? (e) At the equivalence point, after adding 25.00mL of NaOH, what ions or molecules are present in the solution? (f) Which of the species you identified in part (e) will determine…arrow_forward
- 6. A buffer is prepared by adding 20.0 g of sodium acetate (CH3COONa) to 500 mL of a 0.150 M acetic acid (CH3COOH) solution. (A) write the complete ionic equation for the reaction that occurs when a few drops of hydrochloric acid are added to the buffer. (B) Write the complete ionic equation for the reaction that occurs when few drops of sodium hydroxide solution are added to the buffer. Group of answer choices a.) (A) CH3COO-(aq)+ H+ (aq) --->CH3COOH(aq) (B) CH3COOH(aq) + OH-(aq)--->CH3COO-(aq)+H2O(l) b.) (A) Na+ (aq)+ CH3COO-(aq)+ H+ (aq)+CI-(aq) --->CH3COOH(aq)+Na+(aq)+CI-(aq) (B) CH3COOH(aq)+Na+(aq)+ OH-(aq)--->CH3COO-(aq)+H2O(l)+Na+(aq) c.) (A) Na+ (aq)+ CH3COO-(aq)+ H+ (aq)+CI-(aq) --->CH3COOH(aq)+Na+(aq)+CI-(aq) (B) CH3COOH(aq) + OH-(aq)--->CH3COO-(aq)+H2O(l) d.) (A) CH3COO-(aq)+ H+ (aq) --->CH3COOH(aq) (B) CH3COOH(aq)+Na+(aq)+ OH-(aq)--->CH3COO-(aq)+H2O(l)+Na+(aq)arrow_forwardTitration of a 10.0 mL sample of acid rain required 2.1 mL of 0.0824 M KOH to reach the end point. If we assume that the acidity of the rain is due to the presence of sulfuric acid, what was the concentration (in mol/l and %) of sulfuric acid in this sample of rain?arrow_forwardHydroiodic acid often is used to disinfect and sanitize medical tools and products. In an experiment, 5.0 mL of 0.75 mol/L HI(aq) is mixed with 20.0 mL of distilled water. (record only your final answer with the correct number of significant digits and the proper units.) 1. What is the hydronium ion concentration of the resulting diluted solution? 2. What is the pH of the resulting solution? 3. If 1.0 mL of the diluted solution is added to 9.0 mL of distilled water, what is the resulting pH of the solution? 4. If 1.0 mL of the diluted solution from #3 is added to 9.0 mL of distilled water, you should be able to predict the pH based on the trend you see and without doing any calculations. This is because every time the hydronium concentration a) increases b)decreases by a factor of 10, the pH goes up one full unit since the solution becomes a)more b)less acidic.arrow_forward
- The pH scale for acidity is defined by pH – log10 H*| where |H*| is the concentration of hydrogen ions measured in moles per liter (M). (A) The pH of Drano is 13.3. Calculate the concentration of hydrogen ions in moles per liter (M). [H*] = M (B) The pH of rain water is 5.5. Calculate the concentration of hydrogen ions in moles per liter (M). [H*] = Marrow_forwardIn this assignment, you will determine the mass % of an unknown sample of baking soda (NaHCO3) by titrating it with an HCl solution of known concentration. The laboratory will open with a beaker on the stir plate with 1.5000 g of impure solid NaHCO3 and with sufficient water added to make the total volume 25.00 mL. The buret will be filled with 0.3015 M HCl. Pouring HCI until pH is 2. The volume in the buret went from 0 mL to 43 mL Question 1: Calculate the moles of HCl transferred during the titration. (number and unit) (Keep four significant digits in all of the calculations.) Question 2: How many moles of NaHCO3 are present in the sample? Question 3: What mass of NaHCO3 is present in the sample? Question 4: What percent of the original sample mass was NaHCO3?arrow_forwardThe average blood pH is 7.40. The blood volume in humans, on average, is 5 liters. On average bicarbonate concentration in blood is 25 mM. A vinegar jar has a label that says its acetic acid concentration is 3.0%, meaning 3.0 g of acetic acid in 100 mL vinegar. (1) How many mL of vinegar does a person have to intake in order to lower the blood pH to 7.25? (2) if ALL the bicarbonate in 5.0 L of blood is neutralized by vinegar, how many mL of vinegar will be needed? (3) When all the bicarbonate ions are neutralized to carbonic acid, what will be the resulting blood pH? Note: pKa values for carbonic acid (diprotic acid) are 6.4 and 10.3, respectively.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Chemistry: Principles and PracticeChemistryISBN:9780534420123Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward MercerPublisher:Cengage LearningChemistry for Today: General, Organic, and Bioche...ChemistryISBN:9781305960060Author:Spencer L. Seager, Michael R. Slabaugh, Maren S. HansenPublisher:Cengage Learning
- Chemistry: An Atoms First ApproachChemistryISBN:9781305079243Author:Steven S. Zumdahl, Susan A. ZumdahlPublisher:Cengage LearningChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage Learning
Chemistry: Principles and Practice
Chemistry
ISBN:9780534420123
Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer
Publisher:Cengage Learning
Chemistry for Today: General, Organic, and Bioche...
Chemistry
ISBN:9781305960060
Author:Spencer L. Seager, Michael R. Slabaugh, Maren S. Hansen
Publisher:Cengage Learning
Chemistry: An Atoms First Approach
Chemistry
ISBN:9781305079243
Author:Steven S. Zumdahl, Susan A. Zumdahl
Publisher:Cengage Learning
Chemistry
Chemistry
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Cengage Learning
Acid-Base Titration | Acids, Bases & Alkalis | Chemistry | FuseSchool; Author: FuseSchool - Global Education;https://www.youtube.com/watch?v=yFqx6_Y6c2M;License: Standard YouTube License, CC-BY