Which factors directly explain why the rate of a reaction increases when the temperature is increased? I. More of the reacting particles will possess the necessary activation energy. II. The frequency of the collisions increases. III. The value of the average kinetic energy of the particles increases
The correct answer and explanation is:
Correct Answer: I, II, and III
All three factors directly explain why the rate of a chemical reaction increases when the temperature is increased.
Explanation:
Temperature plays a crucial role in determining the rate of a chemical reaction. When the temperature of a system increases, several changes take place at the molecular level that contribute to a higher reaction rate.
Firstly, the average kinetic energy of particles increases (statement III). Temperature is directly related to kinetic energy, and as particles move faster due to this increased energy, they are more likely to collide with each other. Faster-moving particles also result in a higher number of collisions per unit time.
Secondly, the frequency of collisions increases (statement II). With more energy, particles move more rapidly and encounter each other more often. This means that there are more opportunities for reactant particles to collide and form products, which directly contributes to an increased reaction rate.
Thirdly, more of the reacting particles will possess the necessary activation energy (statement I). The activation energy is the minimum energy required for a reaction to occur. At higher temperatures, a greater proportion of the particles will have enough energy to overcome this barrier. Even though not all collisions result in a reaction, the number of successful collisions increases with temperature.
According to the collision theory and the Maxwell-Boltzmann distribution, a rise in temperature shifts the distribution curve such that more particles have energies equal to or greater than the activation energy. This increased population of high-energy particles significantly enhances the probability of effective collisions.
In conclusion, all three statements (I, II, and III) are correct and together explain why increasing temperature leads to a faster reaction rate.