In Bronsted-Lowry theory, an acid is defined as a substance that:

Correct Answer: Donates a proton (H⁺)

Subject: chemistry

Donates an electron pair
Accepts an electron pair
Donates a proton (H⁺)
Accepts a proton (H⁺)

Explanation: • Key Fact According to the Bronsted-Lowry theory, an acid is any species that can donate a proton (H⁺) to another species. • Supporting Detail A Bronsted-Lowry base is defined conversely as a proton (H⁺) acceptor. • Related Concept Example of this acidic behavior is HCl donating H⁺ when dissolved in water. • Why wrong options are wrong Electron pair donation/acceptance relates to the Lewis Theory, not Bronsted-Lowry. • Exam Trick Bronsted = Proton focus. Lewis = Electron focus. • Additional Info Arrhenius theory focuses on increasing H⁺ or OH⁻ concentration in aqueous solutions.