What is the [H₂PO₄^-] of a solution labeled "0.10 M Phosphoric Acid"? [Ka1 = 7.1 × 10^-3; Ka2 = 6.3 × 10^-8; Ka3 = 4.2 × 10^-13] A) 0.023 M B) 6.3 × 10^-8 M C) 7.1 × 10^-3 M D) 4.2 × 10^-13 M E) 0.013 M

Question

Quizplus · Accepted Answer

The concentration of H2PO4- is determined by the first dissociation of phosphoric acid, which is primarily governed by Ka1. Using the approximation that [H+] ≈ √(Ka1 × [H3PO4]), we find [H+] ≈ 0.023 M, which is also the concentration of H2PO4- at equilibrium.

What Is the [H2PO4-] of a Solution Labeled "0

What Is the [H₂PO₄^-] of a Solution Labeled "0