Which of the following illustrates the influence of surface area of a solid reactant on reaction rate ?

Options

A. Powered sugar dissolves faster than crystallune sugar
B. Finely powdered potassium permanganate reacts violently with glycerol than crystalline potassium permanganate
C. Explosion occurs when an inflammable substance is finely dispersed in a room
D. All of these

Answer

D

Explanation

All these statements are correct. In heterogeneous reactions the reactants are present in more than one phase. The rate of such reactions depends upon the surface area of contact between the reactants. The principle is used in the manufacture of exp,osives and rocket fules.
A reaction will proceed faster if the reactants are mixed in the liqiud phase (or solution phase) than when carried out under heterogeneous conditions provided the concentrations are the same. Increasesing the fineness of the solid is an attempt to decrease the heterogeneity of the reaction mixture. This implies that reaction rate depends upon the physical states of reactants.
It is common Knowledge that one stirs tea to dissolve the sugar quickly. The same is true when ew mix two reactants because stirring increases dispersion of one reactant species in the other.