Question

the activation energy for a chemical reaction depends upon:
(A) Temperature
(B) Nature of reacting species
(C) Concentration of the reacting species
(D) Collision frequency

Answer 1

Activation energy is the minimum amount of energy which is required to activate atoms or molecules to a state in which they can undergo any chemical transformation. In other words, we can say that activation energy is the minimum energy required for a reaction to occur. It also helps to determine the rate of reaction.

Complete step by step answer:
It is evident that almost all the chemical reactions do not occur spontaneously and must have an initial input of energy to initiate the reaction. This energy is known as the activation energy. It helps to determine the rate of reactions and also help the atoms to reach their required transition state.
During a chemical reaction, certain chemical bonds are broken and simultaneously certain new chemical bonds are also formed when over a bond breaks, some amount of energy is released. However, it is important to acquire a certain transition stage for facilitating the breakage of the bond. The transition state is a high energy unstable state. As the molecules in their transition state are unstable, thus the molecules do not remain for a long time in this state and quickly proceed further towards the next step of the chemical reaction.
The most common source of the activation energy which is needed to push the reactions forward is the heat energy from the surroundings. This energy speeds up the motion of molecules and does increase the frequency and force of molecules with which they collide. It helps to move the atoms and bonds within a molecule to facilitate the ease with which the atoms can reach their required transition stage. For this reason, heating up a system will cause the chemical reactants within that system to react more frequently. Increasing the pressure on the system. Once the reactants have absorbed enough heat energy, depending on the nature of the atom, from their surroundings to reach the transition state, the reaction will proceed.

So, the correct answer is Option B.

Note: Activation energy must be considered while analysing both endogenic and exogenic reactions. Exogenic reactions do have a not release of energy, but still some amount of energy is required for the imitation of the process.