Question

It takes time for pieces of shahabad tile to disappear in $HCl$ , but its powder disappears rapidly.

Answer 1

Hint : To solve the given problem, we should have information about the Rate of reaction and stoichiometric coefficient. Rate of reaction is the change in concentration of reactant or product per unit time.
The stoichiometric coefficient represents the number that appears before a chemical reactant or formula. Stoichiometric coefficient is also the quantitative relation between the number of moles. Stoichiometric coefficients are said to be negative for reactants and positive for products.

Complete Step By Step Answer:
Step-1 :
When Shahabad tiles are dissolved in $HCl$ , it takes time because they have comparatively less surface area in exposure to the $HCl$ .
Step-2 :
When powdered form is taken, the surface increases as compared to volume and the exposure to $\ HCl$ increases. Furthermore, the rate of chemical reaction is directly proportional to the surface area.

Additional Information:
The other factors responsible for the rate of reaction is :
Concentration of reactant. Increasing the concentration of reactants increases the rate of reaction.
Surface area. The rate of reaction is directly proportional to surface area.
Temperature. Increasing temperature increases the rate of reaction as the average kinetic energy of the reactant molecules increases.
Presence of a catalyst also plays an important role in accelerating or decelerating a chemical reaction.

Note :
Stoichiometry is based on the law of conservation of mass. The law of conservation of mass states that mass can neither be created nor be destroyed only transferred from reactants to products.