What is the correct procedure for mixing acid and water?

Mixing acid and water requires careful attention to safety and proper procedure due to the exothermic reaction that occurs when acid is combined with water. The correct procedure is to add acid slowly to water. This method ensures that the heat generated from the reaction is dissipated more effectively because the water, being the larger volume, can absorb the heat produced as the acid is introduced gradually.

When acid is poured into water, the water helps dilute the acid and manage the heat produced. Conversely, if water were to be poured into concentrated acid, the rapid reaction could cause the acid to splatter or boil violently, posing a significant safety hazard.

Thus, adding acid to water is the safest and most effective approach. This standard practice helps prevent accidents and ensures proper mixing without creating hazardous situations.