Question

give ans in short: Nature of reactants and concentration of the reactants​

Answer 1

Explanation:

Fast reactions include acid reactions, the formation of salts and ion exchange. Reactions tend to be slow when covalent bond formation takes place between the molecules and when large molecules are formed.

Increasing the concentration of the reactants will increase the frequency of collisions between the two reactants. When collisions occur, they do not always result in a reaction (atoms misaligned or insufficient energy, etc.). Higher concentrations mean more collisions and more opportunities for reaction.