What is the difference between the velocity and the speed of an object

The reason is simple. Speed is the time rate at which an object is moving along a path, while velocity is the rate and direction of an object's movement.

Explanation:

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.