If a reaction rate increases with temperature, how will the rate constant of the reaction change with temperature?
A. The rate constant only changes upon addition of a catalyst to the reaction.
B. The rate constant will decrease with temperature.
C. The rate constant will not change with temperature.
D. The rate constant will increase with temperature.
The correct answer is D. The rate constant will increase with temperature. According to the Arrhenius equation, the rate constant of a reaction is directly proportional to the temperature. As the temperature increases, the average kinetic energy of the reactant molecules also increases, leading to more frequent and energetic collisions, resulting in a higher reaction rate. Therefore, the rate constant of a reaction generally increases with temperature.
To determine how the rate constant of a reaction changes with temperature, we need to understand the relationship between reaction rate and temperature.
When a reaction rate increases with temperature, it means that the reactants are converting into products at a faster rate when the temperature is higher. This is due to the increase in kinetic energy of the reactant molecules, leading to more collisions and higher chances of successful reactions.
According to the Arrhenius equation, the rate constant (k) of a reaction is directly proportional to the temperature (T) in Kelvin. The Arrhenius equation is as follows:
k = A * e^(-Ea/RT)
Where:
k = rate constant
A = pre-exponential factor or frequency factor
Ea = activation energy
R = gas constant
T = temperature in Kelvin
e = mathematical constant (approximately equal to 2.71828)
From the Arrhenius equation, we can see that the rate constant increases with temperature because the exponential term in the equation is directly influenced by the temperature term (1/T). As the temperature increases, the value of 1 divided by temperature (1/T) becomes larger, making the exponential term larger, and subsequently increasing the rate constant.
Therefore, the correct answer is D. The rate constant will increase with temperature.