Multiple Choice
What is the pH of a buffered system made by dissolving 17.42 g of KH2PO4 and 20.41 g of K2HPO4 in water to give a volume of 200.0 mL? The Ka2 for dihydrogen phosphate is 6.2 × 10-8 and the equilibrium reaction of interest is H2PO4-(aq) + H2O(l) ⇌ H3O+(aq) + HPO4-(aq) .
A) 7.03
B) 7.17
C) 7.38
D) 7.58
Correct Answer:
Verified
Correct Answer:
Verified
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