What is the [H₃O⁺] in a buffer that consists of 0.30 M HCOOH and 0.20 M HCOONa? For HCOOH, K_a = 1.7 × 10⁻⁴ A)1.1 × 10 ⁻⁴ M B)2.6 × 10 ⁻⁴ M C)4.3 × 10 ⁻⁴ M D)6.7 × 10 ⁻⁵ M E)None of these choices are correct.

Question

Quizplus · Accepted Answer

The concentration of H+ in the buffer can be calculated using the Henderson-Hasselbalch equation: pH = pKa + log([A-]/[HA]), where [A-] is the concentration of the conjugate base (HCOONa) and [HA] is the concentration of the acid (HCOOH). Given pKa = -log(1.7 × 10^-5) and the concentrations, solving for [H+] gives approximately 2.6 × 10^-5 M.

What Is the [H3O+] in a Buffer That Consists of 0.30

What Is the [H₃O⁺] in a Buffer That Consists of 0.30