Q.:- While diluting an acid, why is it recommended that the acid should be added to water and not water to the acid?
The process of dissolving an acid or a base in water is a highly exothermic one. Care must be taken while mixing concentrated HNO3 acid or H2SO4 with water. The acid must always be added slowly to water with constant stirring. If water is added to a concentrated acid, the heat generated may cause the mixture to splash out and cause burns. The glass container may also break due to excessive local heating.