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Question
What is the hydronium-ion concentration of a buffer solution that is 0.50 M Na2HPO4and 0.20 M NaH2PO4? For H3PO4, Ka1= 6.9 x10-3, Ka2= 6.2 x10-8, and Ka3= 4.8 x10-13.
A) 1.7 x10-2M
B) 2.8 x10-3M
C) 1.6 x10-7M
D) 2.5 x10-8M
E) 1.9 x10-13M
Answer
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