1. Chemical Engineering Lab 1
Iodine Reaction
Chemical Engineering Lab 1

2. Objectives
To calculate the order of reaction, rate constant, and activation energy
To study the effect of temperature towards the reaction rate constant

3. Review Let’s look at a iodine reaction: Main reaction Side reaction
K-persulfate
K-sulfate
Side reaction
Na-thiosulfate
Na-tetrathionate
k1 > k2
Main reaction is FASTER than side reaction If
k1 < k2
Main reaction is SLOWER than side reaction

4. Investigate the main reaction
In an ionic reaction form
gas
The equation of rate of reaction becomes:

5. Manipulation
To evaluate “n”, the concentration of KI must be very high (excess) so that it can be considered as constant, hence k1.[KI]m = k*
Using the same way, you can do for evaluating “m”

6. Calculate “n” and “m”
“n” and “m” can be obtained from the experimental data (Iodine Reaction I and II)
However, “k” is depending on T. Evaluate “k” by varying T (Iodine Reaction III)

7. Arrhenius equation
CONSTANT
Use a linear regression method to calculate all the constants

8. Thank you