Question

Click and drag the elements to place the steps required to calculate the activation energy (Ea) from the Arrhenius equation in the correct order. Start with the first step at the top of the list.

a) Identify the rate constant (k)
b) Measure temperature (T)
c) Determine the reaction order
d) Plot the natural logarithm of the rate constant against the reciprocal of temperature

Answer 1

To calculate activation energy using the Arrhenius equation, identify the rate constant (k), measure the reaction temperature (T), plot ln(k) versus 1/T, and use the slope of this graph to determine Ea.

Step-by-step explanation:

To calculate the activation energy (Ea) from the Arrhenius equation, the following steps should be taken in order:

1. Identify the rate constant (k) which is the speed at which a chemical reaction proceeds.
2. Measure temperature (T) where the reaction occurs, as temperature is a crucial factor that affects the rate of reaction.
3. Determine the reaction order, although it's not directly needed for calculating Ea, it's often part of understanding the reaction dynamics.
4. Plot the natural logarithm of the rate constant against the reciprocal of temperature (1/T) to create a graph, which should produce a straight line if the Arrhenius equation is applicable.

Once you have plotted ln(k) against 1/T, the slope of the line can be used to calculate the activation energy. The slope will be equal to -Ea/R where R is the universal gas constant. Multiply the slope by -R to solve for Ea.