Which is a Bronsted acid example?

Which is a Bronsted acid example?

• A. NH3
• B. CO2
• C. HCl
• D. H2O

Answer: (C)

Bronsted acids are substances that donate a proton (H+). In water, hydrochloric acid donates its proton to the water molecule, giving hydronium and chloride: HCl + H2O → H3O+ + Cl−. Because HCl is a strong acid, this proton transfer happens readily and completely, making it a clear and classic example of a Bronsted acid. Ammonia behaves as a Bronsted base because it tends to accept a proton, forming NH4+. Water is amphoteric, capable of both donating and accepting protons depending on the reacting species, so it’s not the most straightforward illustration of a Bronsted acid in this context. CO2 can form carbonic acid in water, but the proton-donating species in that context is carbonic acid, not CO2 itself, so it’s not the typical Bronsted acid example students are asked to recognize.

Bronsted acids are substances that donate a proton (H+). In water, hydrochloric acid donates its proton to the water molecule, giving hydronium and chloride: HCl + H2O → H3O+ + Cl−. Because HCl is a strong acid, this proton transfer happens readily and completely, making it a clear and classic example of a Bronsted acid.

Ammonia behaves as a Bronsted base because it tends to accept a proton, forming NH4+. Water is amphoteric, capable of both donating and accepting protons depending on the reacting species, so it’s not the most straightforward illustration of a Bronsted acid in this context. CO2 can form carbonic acid in water, but the proton-donating species in that context is carbonic acid, not CO2 itself, so it’s not the typical Bronsted acid example students are asked to recognize.