What is an acid-base neutralization reaction?

• A. A reaction between an acid and a base producing a salt and water
• B. A reaction that only releases carbon dioxide
• C. A reaction that breaks water into hydrogen and oxygen
• D. A reaction that forms an acid from a base

Answer: (A)

An acid-base neutralization is a reaction between an acid and a base that yields a salt and water. In solution, the acid donates a proton (H+) and the base provides hydroxide (OH−); when they meet, the H+ and OH− combine to form H2O, and the remaining ions form a salt. A classic example is HCl reacting with NaOH to give NaCl and H2O. This is what makes it neutralization—the acidic and basic properties cancel out to produce a neutral salt and water. The other descriptions don’t describe the typical outcome: releasing carbon dioxide isn’t a general feature of neutralization (it only happens with carbonates in some cases), breaking water apart is electrolysis, and forming an acid from a base describes the reverse or a different process, not the standard salt-and-water product.