Final answer:
In aqueous solutions, H2SO4 (sulfuric acid) and NH4+ (ammonium ion) can behave as Bronsted-Lowry acids because they have the ability to donate protons. The final answer to the multiple-choice question (MCQ) is: H₂SO₄ and NH₄⁺.
Step-by-step explanation:
In the context of Bronsted-Lowry acid-base theory, an acid is defined as a substance that can donate a proton (H⁺) to another substance. Given the options presented, we are looking for substances that can act as proton donors in an aqueous solution:
- ClO4- is a perchlorate ion and does not readily donate a proton, so it is not typically considered a Bronsted-Lowry acid.
- Ba(OH)2 is barium hydroxide, a strong base that dissociates completely in water to give OH- ions and Ba2+ ions, and does not act as an acid.
- H2SO4 is sulfuric acid, a strong acid that can donate two protons in a stepwise manner, clearly acting as a Bronsted-Lowry acid.
- NH4+ is the ammonium ion, which can donate a proton to form ammonia (NH3), thereby behaving as a Bronsted-Lowry acid.
Therefore, both H2SO4 and NH4+ have the ability to behave as Bronsted-Lowry acids in aqueous solution.