A solution of 8.01 M formic acid (HCOOH)is 0.47% ionized.What is the K_a value of formic acid? A)3.8 $\times$ 10^-² B)1.8 $\times$ 10^-⁴ C)4.7 $\times$ 10^-³ D)3.8 E)more data is needed

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Quizplus · Accepted Answer

The degree of ionization is 0.47%, which means [H+] = 0.0047 * 8.01 M. Using the formula Ka = [H+][A-]/[HA], we find Ka = (0.0047 * 8.01)^2 / (8.01 - 0.0047 * 8.01), which approximates to 1.8 x 10^-4.

A Solution of 8 ×\times× 10-2 B)1 ×\times× 10-4 C)4 ×\times× 10-3 D)3

A Solution of 8 $\times$ 10^-²
B)1 $\times$ 10^-⁴
C)4 $\times$ 10^-³
D)3