Given the balanced equation representing a reaction: H2PO4 (aq) + H₂O(1)→ H₃PO₄(aq) + OH(aq) According to one acid-base theory, the H₂O(/) molecules act as (1) a base because it accepts an H (2) a base because it donates an H (3) an acid because it accepts an H (4) an acid because it donates an H