The rate of a reaction depends upon the size of the particles of the reactants taking part in the reaction. The smaller the size of the reactants particles, the more is their total surface area and the faster is the rate of reaction.
In the reaction of dil. HCl with pieces of Shahabad tile, CO2 effervescence is formed amid the tile disappears slowly. On the other hand. CO2 effervescence forms at faster rate with Shahabad tile powder and it disappears rapidly.
