BIOCHEMISTRY BOOKS ALC&MOD MST/ET PKG
1st Edition
ISBN: 9780134172507
Author: APPLING
Publisher: Pearson Education
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Chapter 2, Problem 9P
a. Suppose you wanted to make a buffer of exactly pH 7.00 using KH2PO4 and
Na2HPO4. If the final solution was 0.1 M in KH2PO4, what concentration of Na2HPO4 would you need?
b. Now assume you wish to make a buffer at the same pH, using the same substances, but want the total phosphate molarity ([HPO42- ]+[H2PO4-]) to equal 0.3. What concentrations of the KH2PO4 and Na2HPO4 would be required?
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Consider a buffer solution that contains 0.55 M NH2CH2CO2H and 0.35 M NH2CH2CO2Na. pKa(NH2CH2CO2H)=9.88.
a. Calculate its pH.
b. Calculate the change in pH if 0.155 g of solid NaOH is added to 250 mL of this solution.
c. If the acceptable buffer range of the solution is ±0.10 pH units, calculate how many moles of H3O+ can be neutralized by 250 mL of the initial buffer.
Suppose you wanted to make a buffer of exactly pH 7.00 using KH2PO4 and Na2HPO4. If the final solution was 0.1 M in KH2PO4, what concentration of Na2HPO4 would you need?
(E) Consider an amino acid that has one -amino group (pKa = 9.2), one -carboxyl group (pKa = 1.7) and one ionizable side chain (pKa = 6.2). At which pH range/s would this amino acid be effective as a buffer? If the amino acid shows a net charge of -1 at pH 11 and a net charge of +1 at pH 4, what pKa values would you use to calculate the isoelectric point? At what pH would the net charge be equal to zero?
Chapter 2 Solutions
BIOCHEMISTRY BOOKS ALC&MOD MST/ET PKG
Ch. 2 - Suppose a chloride ion and a sodium ion are...Ch. 2 - Draw two different possible hydrogen-bonding...Ch. 2 - Prob. 3PCh. 2 - 4. What is the pH of each of the following...Ch. 2 - Prob. 5PCh. 2 - The weak acid HA is 2% ionized (dissociated) in a...Ch. 2 - 7. Calculate the pH values and draw the titration...Ch. 2 - What is the pH of the following buffer mixtures?...Ch. 2 - a. Suppose you wanted to make a buffer of exactly...Ch. 2 - Prob. 10P
Ch. 2 - You need to make a buffer whose pH is 7.0, and you...Ch. 2 - Describe the preparation of 2.00 L of 100 glycine...Ch. 2 - Carbon dioxide is dissolved in blood (pH 7.4) to...Ch. 2 - What is the molecular basis for the observation...Ch. 2 - The anno acid arginine ionizes according to the...Ch. 2 - It is possible to make a buffer that functions...Ch. 2 - A student is carrying out a biological preparation...Ch. 2 - Histidine is an amino acid with three titratable...Ch. 2 - Prob. 19PCh. 2 - Prob. 20PCh. 2 - Prob. 21P
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