# Determine Rate and Order of a Reaction

Topics: Order of reaction, Rate equation, Chemistry Pages: 4 (1040 words) Published: March 21, 2012
Trial| [FeCl3] (M)| [KI] (M)| Initial rate (sec -1)|
1| .01| .01| .002246|
2| .01| .005| .001348|
3| .005| .01| .001627|
4| .0075| .005| .001126|
5| .005| .0075| .001267|

Order of Reaction: n=1;m=1
R1/R2=.002246/.001348=k[.01][.01]/k[.01][.005]
1.666172=2n n=1

Rate law Expression:
Rate=k[FeCl3][KI]

Rate Law constant:
Trial 1: .002246=k[.01][.01] k=22.46
Trial 2: k=26.96
Trial 3: k=32.54
Trial 4: k=30.027
Trail 5: k=33.787
Average Rate Constant: Trial1+2+3+4+5=145.774/5=29.1548

Procedure
Obtain and wear goggles. Connect a Colorimeter to Channel 1 of the Vernier computer interface. Connect the interface to the computer with the proper cable. Start the Logger Pro program on your computer. Open the file “25 Rate and Order” from the Advanced Chemistry with Vernier folder. Set up and calibrate the Colorimeter. Prepare a blank by filling an empty cuvette ¾ full with distilled water. Place the blank in the cuvette slot of the Colorimeter and close the lid. If your Colorimeter has a CAL button, set the wavelength on the Colorimeter to 430 nm, press the CAL button. Obtain the materials you will need to conduct this experiment. • Three 25 mL graduated cylinders.

• Approximately 100 mL of 0.020 M KI solution in a 100 mL beaker. • Approximately 100 mL of 0.020 M FeCl3 solution in a separate 100 mL beaker. • Approximately 60 mL of distilled water in a third 100 mL beaker. During this experiment you will conduct 5 trials. This step describes the process for conducting the trials using the Trial 1 volumes. When you repeat this process, use the correct volume for each trial based on the table below.

Trial FeCl3 (mL) KI (mL) H2O (mL)
1 20.0 20.0 0.0
2 20.0 10.0 10.0
3 10.0 20.0 10.0
4 15.0 10.0 15.0
5 10.0 15.0 15.0
Measure 20.0 mL of FeCl3 solution into a 100 mL beaker. Measure 20.0 mL of KI...