[tex]K_a[/tex], the acid dissociation constant, for an acid is [tex]9 \times 10^{-4}[/tex] at room temperature. At this temperature, what is the approximate percent dissociation of the acid in a 1.0 M solution?
A. 0.03%
B. 0.09%
C. 3%
D. 5%
E. 9%
Can you please explain with some details?
Answer (2)
The acid dissociation constant, Ka, is the equilibrium constant for the dissociation of a weak acid into ions. It measures the extent to which the acid dissociates in solution and is a measure of the acid's strength. In this case, the Ka for the acid is 9 ∗ 1 0 − 4.
To calculate the percent dissociation, you need to divide the concentration of the dissociated ions by the initial concentration of the acid and then multiply by 100. Since we have a 1.0 M solution, the percent dissociation would be:
Percent dissociation = (Ka / initial concentration) x 100
Percent dissociation = (9 × 10-4 / 1.0) x 100 = 0.09%
Therefore, the approximate percent dissociation of the acid in a 1.0 M solution is 0.09%, so the correct answer is (B) 0.09%.
The approximate percent dissociation of the acid in a 1.0 M solution with a K a value of 9 × 1 0 − 4 is 3%. Thus, the correct answer is (C) 3%.
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