Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 11: Q70P-c (page 263)

Titrating diprotic acid with strong base.

Prepare a family of graphs for the titration of 50.0 mL of 0.020 0 M H2A with 0.100 M NaOH. Consider the following cases: (a) pK1 = 4.00, pK2 =8.00; (b) pK1 = 4.00, pK2 = 6.00; (c) pK1 = 4.00, pK2 = 5.00

Short Answer

Expert verified

(c) The plot of the for pK1 = 4.00, pK2 =5.00 is shown below

Step by step solution

01

Information given

50.0 mL of 0.020 0 M H2A needs to be titrated with 0.100 M NaOH

. (pK1=4.00, pK2=5.00)

02

Equation need to be used to develop spreadsheet

Fromtable 11.5 the equation for the fraction of titration of diprotic acid (H2A) with strong base (B) is as follows

ϕ=CbVbCaVa=αHA-+2αA2--H+-OH-Ca1+H+-OH-Cb

Other formulas need to be used

H+=10-pHOH-=KwH+αHA-=H+K1H+2+H+K1+K1K2αA2-=K1K2H+2+H+K1+K1K2

03

Spreadsheet to plot curve

Spreadsheet for differentpK1=4.00, pK2=5.00

04

Final plot

From the above spreadsheet the following curve was plotted

05

Develop family of graphs

With reference to SID-135385-11-70P-a, SID-135385-11-70P-b, the following curves were obtained

For pK1 = 4.00, pK2 =8.00(SID-135385-11-70P-a)

For pK1 = 4.00, pK2 =6.00(SID-135385-11-70P-b)

The family of curves will be

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

The dibasic compound B (pKb1 = 4.00, pKb2 = 8.00) was titrated with 1.00 M HCl. The initial solution of B was 0.100 M and had a volume of 100.0 mL. Find the pH at the following volumes of acid added and make a graph of pH versus Va: Va = 0, 1, 5, 9, 10, 11, 15, 19, 20, and 22 mL

11-20. The graph shows the titration curve for a protein containingamino acids with 16 basic and acidic substituents. The curve is smooth without clear breaks because 29 groups are titrated in thepH interval shown. The 29 endpoints are so close together that a nearly uniform rise results. The isoionic point is thepHof the pure protein with no ions present exceptH+ and OH-. The isoelectric point is the pHat which the average charge on the protein is zero. Is the average charge of the protein-positive, negative, or neutral at its isoionic point? How do you know?

Acid-base titration of the protein ribonuclease. [Data from C. T. Tanford and J. D. Hauenstein, "Hydrogen Ion Equilibria of Ribonuclease," J. Am. Chem. Soc. 1956, 78, 5287.]

A procedure to measure the alkalinity (Box 11-1) of home swimming pool water is to titrate a fixed volume of pool water by counting the number of drops of the standard H2SO4to reach the bromocresol green endpoint. Explain what is measured in this titration and why bromocresol green was chosen.

Distinguish the terms end point and equivalence point.

Effect of concentration in the titration of weak acid with strong base.Use your spreadsheet from Problem 11-66 to prepare a family of titration curves for pKa = 6, with the following combinations of concentrations: (a) Ca = 20 mM, Cb = 100 mM; (b) Ca = 2 mM, Cb = 10 mM; (c) Ca = 0.2 mM, Cb = 1 mM.
See all solutions

Recommended explanations on Chemistry Textbooks

Making Measurements

Read Explanation

Chemical Reactions

Read Explanation

Physical Chemistry

Read Explanation

The Earths Atmosphere

Read Explanation

Inorganic Chemistry

Read Explanation

Ionic and Molecular Compounds

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free