EXPERIMENT 3

1
EXPERIMENT 3

• KINETICS
• Rate Law Determination of the Crystal Violet
  Reaction

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Equipment and Chemicals
Water bottle with distilled water
Cuvette
10-mL graduated cylinder
Beaker
3
Equipment (cont.)
Logger Pro program
Serial Box Interface
Vernier Colorimeter
4
To use a colorimeter cuvette correctly

• Handle it only by the top edge of the ribbed
  sides

• Gently wipe the outside surface of the clear
  sides clean and dry with a kimwipe.

• Always position the cuvette the same way in the
  colorimeter

• All solutions should be free of bubbles

Ribbed side
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This is the screen you are going to see once you
open the Crysviol.mbl file from the Chemistry 126
Experiment File.
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To calibrate the the Type 1 colorimeter
Choose Calibrate from the Experiment menu and
click Perform Now
Once you place the blank cuvette in the cuvette
slot of the colorimeter and close the lid, turn
the wavelength knob of the colorimeter to the 0
T position, and type 0 in the edit box
When the displayed voltage reading for Input 1
stabilizes,
click
7
For Reading 2, turn the wavelength knob of the
colorimeter to the Green LED position (565 nm).
Type 100 in the edit box
When the displayed voltage reading for Input 1
stabilizes,
click
8
To initiate the reaction, simultaneously pour the
10-mL portions of crystal violet and 0.050 M NaOH
into a 50-mL beaker and swirl the reaction
mixture.
As soon as the two solutions are poured together
click on collect to start the clock.
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Rinse the cuvette twice with small amounts of
the reaction mixture and then fill it ¾ full.
Wipe the outside of the cuvette, place it in the
slot of the colorimeter, and close the lid.
10
As soon as 1 minute has passed start to collect
data approximately every 0.5 minutes. Stop
collecting when the absorbance reaches 0.08.