Question

An acid is a(n) _____. proton donor neutron acceptor compound that splits OH– ions electron pair donor

Answer 1

An acid is a proton donor, so choice (A) is the most correct. That is, they will release H+ ions when placed into water, or when placed into some sort of solution. This will allow the acid to dissociate into its constituent elements.

Answer 2

Answer is: An acid is a proton donor.
According to Bronsted-Lowry theory acid are donor of protons and bases are acceptors of protons (the hydrogen cation or H⁺).
For example hydrochloric acid (HCl) in reaction with water (H₂O) give one proton to water and become chloride anion (conjugate base Cl⁻).