Question

Choose a balanced equation for the transfer of a proton between dihydrogen phosphate ion and the hydroxide ion. Identify the conjugate acid-base pairs. Determine which side of the reaction is favored.

Options:
A. H2PO4- + OH- → HPO4^2- + H2O (Conjugate pairs: H2PO4-/HPO4^2-, OH-/H2O. Favored side: Right)
B. H2PO4- + OH- → HPO4^2- + H2O (Conjugate pairs: H2PO4-/HPO4^2-, OH-/H2O. Favored side: Left)
C. HPO4^2- + OH- → H2PO4- + H2O (Conjugate pairs: H2PO4-/HPO4^2-, OH-/H2O. Favored side: Right)
D. H2PO4 -(aq) + OH-(aq) ⇌ HPO4 2-(aq) + H2O(l) OH- and H2O H2PO4 - and HPO4 2- products

Answer 1

The balanced equation for the transfer of a proton between dihydrogen phosphate ion and hydroxide ion is H2PO4- + OH- → HPO4^2- + H2O, with the conjugate acid-base pairs being H2PO4-/HPO42- and OH-/H2O. The reaction is typically favored on the right side, forming HPO4^2- and H2O.

Step-by-step explanation:

The balanced equation for the transfer of a proton between dihydrogen phosphate ion (H2PO4-) and the hydroxide ion (OH-) is given by option A: H2PO4- + OH- → HPO42- + H2O. In this reaction, the dihydrogen phosphate ion is acting as an acid because it donates a proton to the hydroxide ion, which is acting as a base because it accepts the proton. Therefore, the conjugate acid-base pairs are H2PO4-/HPO42- and OH-/H2O. Given that water (H2O) is a weaker base than the hydroxide ion (OH-), and HPO42- is a weaker acid than H2PO4-, the favored side of the reaction under normal conditions is the right side, as indicated in option A.