Question

If the temperature of a reaction is increased from 10${}^\circ C$ to 100${}^\circ C$ then how many times the rate of reaction will become?

Answer 1

Hint: The rates of a reaction can be affected by changes in temperature, concentration, and particle size. The reactant particles must collide, for a chemical reaction to occur and by changing the parameters of reaction the rate of collision and in turn the rate of reaction can be increased.

Complete step by step solution:
- As we know, for a chemical reaction to occur reactants must collide each other and not all collisions are successful. Only certain collisions with specific energy and orientation will lead to the formation of products.
- Any factor which can increase the number of collisions between particles of reactants per second is expected to increase the rate of reaction. This change in the rate of reaction can be affected by changes in temperature, concentration, and particle size.
- In the question change in temperature is involved. As the temperature is increased the kinetic energy of molecules will increase and this will increase the collision between reactant molecules and thus the rate of reaction will be increased.
- According to the studies, the rate of reaction is not directly proportional to the temperature, instead a 10${}^\circ C$rise in temperature will roughly double the rate of reaction. The increase in the rate of reaction according to the temperature can be given by ${{2}^{n}}$ where n is obtained by dividing the temperature difference of reactions by 10. In the given question the temperature is increased from 10${}^\circ C$ to 100${}^\circ C$.
\[n=\dfrac{100-10}{10}=\dfrac{90}{10}=9\]
Therefore ${{2}^{n}}$ becomes${{2}^{9}}$.

Thus the rate of reaction will increase by ${{2}^{9}}$ times when the temperature is changed from 10${}^\circ C$ to 100${}^\circ C$.

Note: It should be noted that the temperature is a measure of the average kinetic energy of the particles of a substance and energy distribution diagrams can be used to explain the effect of changing temperature on the kinetic energy of particles and rate of a reaction.