Chemistry: You have solutions of 0.200 M HNO2 and 0.200 M KNO2 (Ka for HNO2 = 4.00 * 10^–4). A
buffer of pH 3.000 is needed. What volumes of HNO2 and KNO2 are required to make 1
liter of buffered solution?
A) 500 mL of each
B) 286 mL HNO2; 714 mL KNO2
C) 413 mL HNO2; 587 mL KNO2
D) 714 mL HNO2; 286 mL KNO2
E) 587 mL HNO2; 413 mL KNO2

Question

You have solutions of 0.200 M HNO2 and 0.200 M KNO2 (Ka for HNO2 = 4.00 * 10^–4). A
buffer of pH 3.000 is needed. What volumes of HNO2 and KNO2 are required to make 1
liter of buffered solution?
A) 500 mL of each
B) 286 mL HNO2; 714 mL KNO2
C) 413 mL HNO2; 587 mL KNO2
D) 714 mL HNO2; 286 mL KNO2
E) 587 mL HNO2; 413 mL KNO2

Chemistry · Accepted Answer

ANS: D 
PTS: 1 DIF: Difficult REF: 15.2
KEY: Chemistry | general chemistry | acids and bases | solutions of a weak acid or base
with another solute | buffer | Henderson-Hasselbalch equation

Chemistry

ANS: D PTS: 1 DIF: Difficult REF: 15.2 KEY: Chemistry | general chemistry | acids and bases | solutions of a weak acid or base with another solute | buffer | Henderson-Hasselbalch equation

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