Question

rate of reaction decreases as the reaction proceed . explain how

Answer 1

the rate of reaction decreases as the the reaction process further, this is due to the amount /availability of reactant .
initially the amount of reactant is high , or only reactant molecule present so they can easily approch each other
but as the reaction process the amount of reactant decreases ,
this result decrease in the collision of reactant molecule
so if the molecule could not approch each other or do not collide in proper oriantation , then the product will not form faster and rate of reaction decrease.