Calculate the pH of a0.010Msolution of each amino acid in the form drawn here


Short Answer

Expert verified

The isoionic Ph is =10.37

Step by step solution

01

Step 1: Define the term isoionic ph.      

When a pure, neutral polyprotic acid is dissolved in water, the isoionic point or isoionic pH is obtained.

The isoelectric point is the pH at which the polyprotic acid's average charge is zero (0).

02

Calculate the isoionic PH

The pH of a neutral, polyprotic molecule in pure solution.

The only ions present areH+,OH-

Isoionic is the name given to polyprotic species.

H+=K2K3F+K2KwK2+F

Where F is the formal concentration.

Here Arginine has four forms H3A2+,H2A+,HAandA-

HA form shown as

H+=K2K30.010+K2KwK2+0.010

=4.28×10-11MpH=10.37

Thus the isoionic Ph is=10.37

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.

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

How many millilitres of 1.00 M KOH should be added to 100 mL of solution containing 10.0 g of histidine hydrochloride

[His? HCI (HisH1) (CI2), FM 191.62 ] to get a pH of 9.30 ?

  1. Fractional composition in a tetraprotic system. Prepare a fractional composition diagram analogous to Figure 10-4 for the tetraprotic system derived from hydrolysis of Cr+:

localid="1654853037629" Cr3++H2OCrOH2++H+Ka1=10-3.80CrOH2++H2OCrOH2++H+Ka2=10-6.40CrOH2++H2OCrOH3aq+H+Ka3=10-6.40CrOH3aq+H2OCrOH4-+H+Ka4=-11.40

(Yes, the values oflocalid="1654853051658" Ka2andlocalid="1654853058271" Ka3are equal.)

(a) Use these equilibrium constants to prepare a fractional composition diagram for this tetraprotic system.

(b) You should do this part with your head and your calculator, not your spreadsheet. The solubility of is given by

localid="1654853063951" CrOH3SCrOH3aqKa3=10-6.80

What concentration of localid="1654853075036" CrOH3aqis in equilibrium with solid localid="1654853085944" CrOH3aqS?

(c) What concentration oflocalid="1654853094735" CrOH2+is in equilibrium with localid="1654853101499" CrOH3aqSif the solution localid="1654853109266" pHis adjusted tolocalid="1654853117749" 4.00?

(a) Copy column B of your spreadsheet and paste it into columnG. ChangeK1to10-4in cell G5 and change K2 to 10-8 in cell G6. Change F to 0.01 in cell G8. Column G now contains concentrations for the amphiprotic salt Na+HA-withK1=10-4,K2=10-8, andF=0.01M. Check the answers by hand beginning with pH=12(pK1+pK2). With[HA-],F, calculate[H2A]and[A2-]. Then find[HA-]>>F-[H2A]-[A2-].

(b) Copy column G of your spreadsheet and paste it into column H. Change K2 to 10-5 in cell G6. Column G now contains the concentrations for the intermediate form of a diprotic acid with K1=10-4, K2=10-5, and F =0.01M. You should observe[HA-]=6.13×10-3Mand pH=4.50.

Consider the diprotic acidH2AwithK1=1.00×10-4andK2=1.00×10-8.Find the pH and concentrations ofH2A,HA-, andA2-in

(a)role="math" localid="1654926233413" 0.100MH2A;

(b) role="math" localid="1654926403235" 0.100MNaHA ;

(c) 0.100MNa2A .

Heterogeneous equilibrium.CO2dissolves in water to give "carbonic acid" (which is mostly dissolvedCO2, as described in Box 6-4).

CO2(g)𝆏CO2(aq)K=10-1.5

(The equilibrium constant is called the Henry's law constant for carbon dioxide, because Henry's law states that the solubility of a gas in a liquid is proportional to the pressure of the gas.) The acid dissociation constants listed for "carbonic acid" in Appendix G apply toCO2(aq). Given thatPCO2in the atmosphere is 10-3.4atm, find the pHof water in equilibrium with the atmosphere.

See all solutions

Recommended explanations on Chemistry Textbooks

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