A 25.0 mL sample of 0.723 M HClO4 is titrated with a 0.273 M KOH solution. The H3O+ concentration after the addition of 66.2 mL of KOH is M. a. 0.723
b. 1.00 × 10-7
c. 2.81 × 10-13
d. 0.439
e. 0.273

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explanation:

b is the correct answer

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