What Type of Reaction Is the Formula HCl Plus NaOH Yields H2O Plus NaCl?
The reaction in which hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH) to produce water (H2O) and sodium chloride (NaCl) is a special type of double displacement reaction called a neutralization reaction. In a double displacement reaction, the anions of the reactants switch the cations they are associated with.
The reactant HCl forms a cation, H+, and an anion, Cl-, in an aqueous solution. Sodium hydroxide forms a cation, Na+, that is associated with OH- on the reactant side. When the reaction proceeds to the product side, Na+ switches the anion it is associated with from OH- to Cl-, thus yielding NaCl. Similarly, H+ switches its anion from Cl- to OH- to form water (H2O). Since both the anions are being displaced from their original cations, this reaction is called a double displacement reaction.
This special kind of double displacement reaction is called a neutralization reaction because HCl is an acid and NaOH is a base, and they neutralize each other to form water and a salt after the reaction.