A bimolecular reaction is always a second-order reaction, but a second-order reaction is not always a bimolecular reaction.
The most important thing to take note of is that molecularity of a reaction is a concept applicable to only elementary reactions, meaning non-complex. In a way, elementary reactions are basic and achieved in one step. Complex reactions involve intermediate steps before achieving the desired reaction.
Molecularity is equal to the sum of the coefficients of the reactants, so two reactants give a second-order bimolecular reaction. However, second-order reactions can involve more than two reactants especially in complex reactions.
The more energy needed, the higher the melting point or boiling point . Since the electrostatic forces of attraction between oppositely charged ions are strong, their melting and boiling points are high.
Kinetic energy is the energy possessed by a body while in motion. Potential energy on the other hand is the energy possessed by a body based on its position.
Kinetic energy of a body is determined by the equation; K.E = 3RT/2;
From the equation, kinetic energy is directly proportional to the temperature of the system and therefore an increase in the kinetic energy of a sample causes an increase in temperature of the system.