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Question
Which of the following is the most effective buffer system for a pH value of 4.45?
A) H2CO3/HCO3- (Ka1 for H2CO3 is 4.3 x10-7)
B) HCO3-/CO32- (Ka2 for H2CO3 is 4.8 x10-11)
C) H2S/HS- (Ka1 for H2S is 8.9 x10-8)
D) HC2O4-/C2O42- (Ka2 for H2C2O4 is 5.1 x10-5)
E) H3PO4/H2PO4- (Ka1 for H3PO4 is 6.9 x10-3)
Answer
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