Activity 2.10 NCERT Class 10 Science, Chapter 2 Acids, Bases, and Salts
Activity 2.10 asks us to add a few drops of concentrated sulphuric acid slowly into a beaker containing water and see if heat produces.
When we touch the bottom of the beaker, it feels hot
Diluting an acid or base into water is an exothermic reaction. Here hydrogen ion interacts with a water molecule and forms hydronium ion. In this process, heat evolves which make the beaker hot.
H2SO4 ——> H+ + HSO4–
H+ + H2O ——> H3O+
- We add acid to water. If we add water to acid, the high concentration of acid may produce a violent exothermic reaction.
- Concentrated acids and bases are corrosive; no person should touch it with bare hand or skin. In case a few drops spill on the body, a person should wash it with plenty of water.
Ref: Hydronium ion.