Which compound should never be stored with NaOH?

When considering the compounds that should never be stored with sodium hydroxide (NaOH), hydrochloric acid (HCl) is particularly hazardous due to the highly exothermic reaction that occurs when these two substances come into contact. When NaOH, a strong base, reacts with HCl, a strong acid, it produces sodium chloride (NaCl) and water (H₂O), releasing a significant amount of heat in the process. This reaction can lead to boiling and splattering of corrosive materials, posing safety risks such as chemical burns and potential damage to storage facilities.

Furthermore, the presence of sodium hydroxide can lead to the release of gas or create pressure if not properly managed, making it critical to ensure that incompatible substances like acids are stored separately. Safe chemical storage practices dictate that strong acids and bases, such as HCl and NaOH, should always be kept apart to prevent accidental reactions that can cause personal injury or significant property damage.

In contrast, water, calcium chloride (CaCl₂), and methanol (CH₃OH) do not present the same type of risk when stored with NaOH, as their chemical interactions do not produce hazardous conditions or violent reactions. This makes them more suitable for storage alongside NaOH, although