Choose the buffer with the greatest buffering  capacity:     d. 0.25M formic acid/formate buffer at pH 3, pKa 3.75   b. 0.25M  HEPESH+/HEPES buffer at pH 10, pKa = 8.08   c. 0.75M acetic acid/acetate buffer at pH 4.76, pKa = 4.76   a. 1M acetic acid/acetate buffer at pH 4.76, pKa = 4.76

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A buffer is prepared by mixing equal volumes of 0.075 M sodium acetate(NaC2H3CO2) of a 0.150 M acetic acid (H C2H3CO2, Ka = 1.8  10-5) solution. Write an equation for the reaction that occurs when a few drops ofhydrochloric acid are added to the buffer. Write an equation for the reaction that occurs when a few drops of sodiumhydroxide solution are added to the buffer.

For a titration of 50.0 mL of 0.100 M acetic acid with 0.100 M NaOH, calculate pH: 1. at 0.00 mL NaOH addition (pH=2.87) 2. at 10.00 mL NaOH addition (pH=4.14) 3. at 25.00 mL NaOH addition (pH=4.74) 4. at 50.00 mL NaOH addition (pH=8.72) 5. at 51.00 mL NaOH addition (pH=11.00)

Buffers will resist pH changes following the addition of acid or base within about +/-1 pH unit of the pka of a solution. True False

You have 0.500 L of an 0.250 M acetate buffer solution (i.e. [HC2H3O2] + [C2H;O2] = 0.250 M) at pH 3.50. How many mL of 1.000 M NaOH must you add in order to change the pH to 5.37? Acetic acid has a pka of 4.74. mL 1 2 3 4 C 7 8 9. +/- х 100 +

Your goal is to make a buffer with a pH of 4.75 from acetic acid and sodium acetate.  Assume the pKa for acetic acid is 4.74.  What is the volume of 1 M sodium acetate added to make your buffer? Report your answer to the tenths place.   To do this, we use the Henderson-Hasselbach Equation pH = pkA + log (base/acid) where pkA = 4.74 for acetic acid,  pH = target pH and [base] /[acid] = x/(1-x)  since we don't know the concentration of the base, we will call it x  the acid is just 1-x, assuming the two add  up to 100% solve for x, and then you know the mL of base and acid to add.

Imagine you are working in the lab, and your labmate Jordan has challenged you to figure out which one of the  following acetic acid/sodium acetate buffer solutions has the greatest buffering capacity at a pH above 4.74. pKa(acetic acid) = 4.74. Can you pick the solution with the highest buffering capacity at a pHabove 4.74? pKa(acetic acid) ?     0.36 M acetic acid and 0.12 M sodium acetate         0.16 M acetic acid and 0.12 M sodium acetate         0.36 M acetic acid and 0.22 M sodium acetate         0.16 M acetic acid and 0.22 M sodium acetate

11,The equivalence point of titrating of the weak base with the strong acid will be observed at Group of answer choices A, pH>7 B, pH<7 C, pH=pKb D, pH>pKb E, pH=7   12,The titration curve of titrating a diprotic acid with a strong base will have two distinct equivalence points  Group of answer choices A, if Ka1<<Ka2 B, if Ka1=Ka2 C, always D, in case of ta strong acid E, if Ka1>>Ka2

What volume of stock 0.350 M KOH and what mass of N-2-Hydroxyethylpiperazine-N′-2-ethanesulfonic acid (HEPES, MW 238.30, pKa 7.56) is needed to prepare 100.0 mL 0.100 M buffer at pH 7.20?