fill in the blank question\na proton (h⁺) donor, or a chemical that releases protons into solution, is a(n)

Brief Explanations:

In chemistry, an acid is defined as a substance that donates protons (H⁺) to a solution. This is based on the Arrhenius, Brønsted - Lowry, and Lewis acid - base theories where the proton - donating property is a key characteristic of acids.

Answer:

acid