The Acidic Ingredient in Vinegar Is Acetic Acid $\times$ 10^-5
B)5 $\times$

The acidic ingredient in vinegar is acetic acid.If the pH of a particular brand of vinegar is 2.40 and the molar concentration of acetic acid in the vinegar is 0.85 M,determine the value of K_a for acetic acid.

A) 2.5 $\times$ 10^-5
B) 5.0 $\times$ 10^-5
C) 4.7 $\times$ 10^-3
D) 1.9 $\times$ 10^-5
E) 7.4 $\times$ 10^-3