A 0050 M Solution of the Weak Acid HA Has [H₃O⁺]

question 99

Multiple Choice

A 0.050 M solution of the weak acid HA has [H₃O⁺] = 3.77 × 10^-4 M. What is the K_a for the acid?

• A) 7.5 × 10^-3 M
• B) 2.8 × 10^-6 M
• C) 7.0 × 10^-7 M
• D) 7.0 × 10^-8 M
• E) 2.6 × 10^-11 M

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