Jisoo was tasked to ensure that an enzyme responsible for keeping her species from extinctior remains biologically active. To do so, she needs to store it in a buffer solution with pH 10.00 Unfortunately, only three acids with their corresponding conjugate base salts are available in thei laboratory as shown below. Ка Conjugate Base Salt Benzoic acid, CsHsCOOH 6.25 x 105 NACSHSCOO Boric acid, H3BO3 5.81 x 107 NaH2BO3 Hydrogen cyanide, HCN 6.20 X 10°10 NACN 1. In what buffer system will Jisoo store the enzyme? 2. Write the dissociation reaction involved in the buffer system. 3. Write the pertinent chemical equations to illustrate what happens upon the addition of smal amounts of (a) strong base and (b) strong acid. 4. Calculate the relative amounts of the buffer components if you were to prepare 250 mL of a 90 mM buffer pH 10.00 using 100 mM stock solutions of its components.

Jisoo was tasked to ensure that an enzyme responsible for keeping her species from extinctior remains biologically active. To do so, she needs to store it in a buffer solution with pH 10.00 Unfortunately, only three acids with their corresponding conjugate base salts are available in thei laboratory as shown below. Ка Conjugate Base Salt Benzoic acid, CsHsCOOH 6.25 x 105 NACSHSCOO Boric acid, H3BO3 5.81 x 107 NaH2BO3 Hydrogen cyanide, HCN 6.20 X 10°10 NACN 1. In what buffer system will Jisoo store the enzyme? 2. Write the dissociation reaction involved in the buffer system. 3. Write the pertinent chemical equations to illustrate what happens upon the addition of smal amounts of (a) strong base and (b) strong acid. 4. Calculate the relative amounts of the buffer components if you were to prepare 250 mL of a 90 mM buffer pH 10.00 using 100 mM stock solutions of its components.

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter4: Acids And Bases

Section: Chapter Questions

Problem 4.35AP: The sec-butyl cation can react as both a Brnsted-Lowry acid (a proton donor) and a Lewis acid (an...

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Write the base ionization constant expression for the ionization of each of the following bases. In each case, the nitrogen atom accepts the proton. a. CH3NH2 (methylamine) b. C2H5NH2 (ethylamine)
The sec-butyl cation can react as both a Brnsted-Lowry acid (a proton donor) and a Lewis acid (an electron pair acceptor) in the presence of a watersulfuric acid mixture. In each case, however, the product is different. The two reactions are as follows: (a) In which reaction(s) does this cation react as a Lewis acid? In which reaction(s) does it react as a Brnsted-Lowry acid? (b) Write Lewis structures for reactants and products and show by the use of curved arrows how each reaction occurs.
. How is the strength of an acid related to the fact that a competition for protons exists in aqueous solution between water molecules and the anion of the acid?
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