Neutralization involves a reaction between H3O+ and?

Neutralization is a chemical reaction that involves the combination of an acid and a base to form a salt and water. In this case, the acid is H3O+ (hydronium ion), which is a characteristic of acidic solutions, and the base is OH- (hydroxide ion), which is a characteristic of basic solutions. Therefore, the correct answer is OH-. When an acid and a base are mixed, they react to form water and a salt. The hydronium ion (H3O+) donates a proton (H+) to the hydroxide ion (OH-) to form water (H2O), which leaves behind the conjugate base of the acid (in this case, it would be H2O).