When HCl is added to Shahabad stone effervescence of CO2 is formed.
The CO2 effervescence is formed slowly with the pieces of Shahabad tiles while at the faster speed with the speed This is because the rate of a reaction depends upon the size of the particles of the reactants taking part in the reaction. Smaller the size of the reactant particles , higher is the rate of reaction. Hence, It takes time for pieces of Shahabad tile to disappear in HCl, but its powder disappears rapidly.
