When values of K_a are small (e.g., 1 $\times$ 10^-5) and concentrations of weak acids [HA] are relatively large (e.g., 0.10 M), the hydronium ion concentration of the solution can be calculated using which expression?

Question

Quizplus · Accepted Answer

The correct expression for calculating the hydronium ion concentration in a solution of a weak acid, when the acid dissociation constant (Ka) is small and the concentration of the weak acid ([HA]) is relatively large, is given by the square root of the product of the acid dissociation constant and the acid concentration, i.e., $[H_3O^+] = \sqrt{Ka[HA]}$. This is represented in choice C.

When Values of Ka Are Small (E ×\times× 10-5) and Concentrations of Weak Acids [HA] Are Relatively Large

When Values of K_a Are Small (E $\times$ 10^-5) and Concentrations of Weak Acids [HA] Are Relatively Large