In an introductory acid–base context, an acid spill can be neutralized most appropriately by adding which of the following?

• A. A base such as sodium bicarbonate ($N_a{H}_0{C}_{O_3}$)
• B. A strong acid such as hydrochloric acid ($HCl$)
• C. An oxidizing agent such as hydrogen peroxide ($H_2{O}_2$)
• D. A neutral salt such as sodium chloride ($N_{a}Cl$)

Answer: (A)

Verified step by step guidance

1. Understand that an acid spill involves the presence of excess hydrogen ions (H\textsuperscript{+}) in the solution, making it acidic.
2. Recall that neutralization is a chemical reaction where an acid reacts with a base to form water and a salt, effectively reducing the acidity.
3. Identify that adding a base will provide hydroxide ions (OH\textsuperscript{−}) which react with the hydrogen ions (H\textsuperscript{+}) from the acid to form water (H\textsubscript{2}O), thus neutralizing the acid.
4. Recognize that sodium bicarbonate (NaHCO\textsubscript{3}) is a mild base that can safely neutralize acids by reacting to form water, carbon dioxide, and a salt, making it appropriate for acid spills.
5. Note that adding a strong acid, an oxidizing agent, or a neutral salt will not neutralize the acid spill; instead, they may worsen the situation or have no effect on acidity.