Question

In the following reaction identify each reactant as an Arrhenius acid or an Arrhenius base and explain your answers.
NaOH + HCl → NaCl + H2O

Answer 1

An Arrhenius acid is a substance that dissociates in water to form hydrogen ions (H+); that is, an acid increases the concentration of H+ ions in an aqueous solution:
HCl = H+ + Cl
An Arrhenius base is a substance that dissociates in water to form hydroxide (OH−) ions; that is, a base increases the concentration of OH− ions in an aqueous solution:
NaOH = Na+ + OH-
This causes the protonation of water, or the creation of the hydronium (H3O+) ion. Thus, in modern times, the symbol H+ is interpreted as a shorthand for H3O+, because it is now known that a bare proton does not exist as a free species in aqueous solution. The Arrhenius definitions of acidity and alkalinity are restricted to aqueous solutions, and refer to the concentration of the solvent ions