3. Vanadic acid is often used as a biological buffer when studying enzymes. You are asked to prepare 100.0 mL of a pH=9.17 buffer, but quickly realize you have only the following available to you: 3.0 M vanadic acid (H₂VOA), 1.0 g sodium dihydrogen vanadate (NaH₂VO4; MW=139.944 g/mol), 2.5 M disodium hydrogen vanadate (Na₂HVOA), and a full bottle of solid sodium vanadate (Na,VO; 183.9085 g/mol). Describe how you would prepare the buffer with the available chemicals. You also have all the water and plassware you want. Ko1 = 1.0 x 10, Ka2 = 2.8 x 10º and Kas = 5.0 x 10:¹5 for H₂VOA. Kw = 1.0 x 10¹4. H

3. Vanadic acid is often used as a biological buffer when studying enzymes. You are asked to prepare 100.0 mL of a pH=9.17 buffer, but quickly realize you have only the following available to you: 3.0 M vanadic acid (H₂VOA), 1.0 g sodium dihydrogen vanadate (NaH₂VO4; MW=139.944 g/mol), 2.5 M disodium hydrogen vanadate (Na₂HVOA), and a full bottle of solid sodium vanadate (Na,VO; 183.9085 g/mol). Describe how you would prepare the buffer with the available chemicals. You also have all the water and plassware you want. Ko1 = 1.0 x 10, Ka2 = 2.8 x 10º and Kas = 5.0 x 10:¹5 for H₂VOA. Kw = 1.0 x 10¹4. H

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

See similar textbooks

Similar questions

7.7 g of citric acid (MM = 192.1 g/mol) can be titrated with NaOH according to the following balanced chemical equation. H3C6H5O7 (aq) + NaOH(aq) → H2O(l) + Na H2C6H5O7(aq) what would the curve for the titration of the neutralization of the three hydrogens of this acid with NaOH look like?
This is another titration question. When 35.00 ml of phosphoric acid of unknown concentration is titrated with 1.025 M NaOH, and 18.75 ml of NaOH is required to reach the endpoint, what is the molarity of the phosphoric acid? The reaction is: H3PO4 (aq) + 3 NaOH (aq) → Na3PO4 (aq) + 3 H2O (l)
A chemistry graduate student is given 250. mL of a 1.50M hydrocyanic acid (HCN) solution. Hydrocyanic acid is a weak acid with K,=4.9 × 10 1º. What mass of NaCN should the student dissolve in the HCN solution to turn it into a buffer with pH = 8.84? You may assume that the volume of the solution doesn't change when the NaCN is dissolved in it. Be sure your answer has a unit symbol, and round it to 2 significant digits. ?
An alkaline earth hydroxide, M(OH)2, was taken to lab for analysis. The unknown powder was poured into a flask and swirled in room temperature DI water until a saturated solution formed. This solution was then slowly filtered to remove the undissolved solid hydroxide. 11.9 mL of this saturated solution was titrated with 0.148 M HCI (ag). Endpoint required 15.6 mL of the HCl (ag) solution. Calculate the Kan for this alkaline earth hydroxide.
4. A solution prepared to be initially 1 M in NH3 and 0.5 M in HCl is (Kb for NH3 = 1.8 x 10¯5): (A) a solution with a pH less than 7 that is not a buffer solution (B) a buffer solution with a pH between 4 and 7 (C) a buffer solution with a pH between 7 and 10 (D) a solution with a pH greater than 7 that is not a buffer solution (E) a solution with a pH of 7
2. Using the procedure described in this module, a student determined the percent KHP in an impure sample of KHP. A 3.150-g sample of impure KHP required 41.50 mL of 0.1352M NaOH solution for titration. (a) Calculate the number of moles of NaOH required for the titration. (b) Calculate the number of moles of KHP present in the impure sample of KHP. (c) Calculate the number of grams of KHP present in the impure sample. (d) Calculate the percent of KHP in the impure sample, using Equation 8. Equation 8: percent KHP in the impure sample, % = ( mass of KHP in the sample,g/ mass of sample analyzed, g) (100%)
bconsider the titration of 25.0 ml. of 0.070 M HCN with 0.080 M NaOH. What volume of base, in milliliters, is required to reach the equivalence point? Volume 21.87✔ mL The equivalence point for a reaction is the point at which one reactant has been completely consumed by addition of another reactant. Thus n(HCN) n(NaOH) [HCN] × V(HCN)= [NaOH] × V(NaOH) V(NaOH)22 mL Consider the titration of 25,0 ml of 0.070 M HCN (K, 4.0 x 10-10) with 0.080 M NaOH. What is the pH before any NaOH is added? pH initial what is the pH at the halfway point of the titration? pit at halfway- What is the pH when 95% of the NaOH required to reach the equivalence point has been added pH when 95% is added- What is the pH at the equivalence point? pet at the equivalence point- Correct Submit
33. Consider a buffer solution that contains 0.45 M HCOOH and 0.55 M NaHCOO. Note that the Ka for formic acid (HCOOH) is 1.8 x 104. (a) Calculate the pH of this buffer solution. pH = (b) Write the net ionic chemical equation that occurs when potassium hydroxide (KOH) (MW of KOH = 56.1 g/mol) is added to the buffer. (c) If 0.260 g of solid KOH is added to 250. mL of this buffer solution, what is the resulting pH of the solution? New pH =
An aqueous solution contains 0.29 M ammonia. One liter of this solution could be converted into a buffer by the addition of: (Assume that the volume remains constant as each substance is added.) 0.15 mol Ba(OH)2 O 0.30 mol NH4Br 0.30 mol HNO3 O 0.29 mol BaBr2 0.15 mol HNO3
A chemistry graduate student is given 100. mL of a 0.90M hydrocyanic acid (HCN) solution. Hydrocyanic acid is a weak acid with K,=4.9 × 10 10 What mass of KCN should the student dissolve in the HCN solution to turn it into a buffer with pH = 8.97? You may assume that the volume of the solution doesn't change when the KCN is dissolved in it. Be sure your answer has a unit symbol, and round it to 2 significant digits.
42. A buffer is prepared using acetic acid, CH3COOH, (a weak acid, pKa = 4.75) and sodium acetate, CH3COONa (which provides acetate ions, the conjugate base), according to the following proportions: Volume of CH3COOH(aq): 139.0 mL Concentration of CH3COOH(aq): 1.103 M Volume of CH3COONa(aq): 127.0 mL Concentration of CH3COONa(aq): 1.259 M Calculate the pH of this buffer after the addition of 20.00 mL of 3.00 M sodium hydroxide, NaOH, a strong base. 4.38 5.90 4.69 4.81 5.12
b) What is the mass of solute in a 500mL solution of HCI that has been diluted from 3.50M to 1.60M? 5 Before toothpaste was invented, people sometimes used calcium carbonate, Cac clean their teeth. What mass of calcium carbonate can be precipitated by react of a 0.100M solution of sodium carbonate, Na₂CO3(aq), with 50.0 mL of a 0.1