When an Arrhenius acid is dissolved in water, it produces which of the following as the only positive ion in solution?

When an Arrhenius acid is dissolved in water, it produces which of the following as the only positive ion in solution?

• A. NH3+ as the only positive ion in solution
• B. H+ as the only positive ion in solution
• C. OH- as the only negative ion in solution
• D. HCO3- as the only negative ion in solution

Answer: (B)

When an Arrhenius acid dissolves in water, it donates a proton (H+), increasing the concentration of positive charges in the solution. In water, that free proton is immediately hydrated to form the hydronium ion, H3O+. So the species carrying the positive charge in the solution is effectively the proton as H3O+ (often simplified to H+ in many depictions). This is why the description of the positive ion as H+ in solution is the best answer. The other options describe species that aren’t produced by dissolving a typical Arrhenius acid in water: a positively charged ammonia species isn’t formed from acid dissolution in this context; hydroxide is a negatively charged ion and comes from bases, not acids; bicarbonate is also a negatively charged ion, not the positive charge carrier.

When an Arrhenius acid dissolves in water, it donates a proton (H+), increasing the concentration of positive charges in the solution. In water, that free proton is immediately hydrated to form the hydronium ion, H3O+. So the species carrying the positive charge in the solution is effectively the proton as H3O+ (often simplified to H+ in many depictions). This is why the description of the positive ion as H+ in solution is the best answer.

The other options describe species that aren’t produced by dissolving a typical Arrhenius acid in water: a positively charged ammonia species isn’t formed from acid dissolution in this context; hydroxide is a negatively charged ion and comes from bases, not acids; bicarbonate is also a negatively charged ion, not the positive charge carrier.