Students will investigate Le Chatelier’s principle and why it works. They will also investigate this principle by testing several systems at equilibrium and then selecting specific ones to produce the colors of the rainbow based on specific applications of Le Chatelier’s principle. Students will then be challenged by selecting which reaction system to use for which color in producing the rainbow while trying to only use a given “stress” once. The activity contains enough materials for 15 groups of students as well as a Teacher’s Guide and Student Study Guide Copymasters. Meets Big Idea 6, Investigation 13, Primary Learning Objective 6.9.

Kit Includes:
3 X 30mL Bromothymol Blue, 0.04%
3 X 15mL Hydrochloric Acid, 0.1N
3 X 15mL Sodium Hydroxide, 0.1N
3 X 15mL Sodium Chloride, 0.1M
3 X 250mL Potassium Thiocyanate, 0.1M
3 X 15mL Ferric Nitrate, 0.2M Fe(No)3
3 X 10g Potassium Thiocyanate
3 X 10g Iron(III)Chloride
3 X 10g Sodium Phosphate Tribasic
3 X 15mL Potassium Nitrate, 0.1M
3 X 250mL Copper (II) Sulfate
3 X 15mL Hydrochloric Acid, 1.0N
3 X 15mL Ammonium Hydroxide, ACS 28-30%
3 X 10g Copper(II)Chloride
3 X 15mL Hydrochloric Acid, T/G 32%
3 X 10g Cobalt Chloride Hexahydrate
3 X 250mL Ethyl Alcohol, R/G 95% Denatured
3 X 30mL Deionized Water
3 X 30mL Acetone
3 X 10g Sodium Chloride
3 X 15mL Methyl Red Indicator, 0.3%
3 X 15mL Silver Nitrate, 0.1M

**Materials needed but not supplied:
Beaker, 250mL
Beaker, 50mL
Graduated Cylinder, 10mL
Graduated Cylinder, 50mL
Hot Plate
Ice
Labeling or Marking Pens
Magnetic Stir Plate
Stir Bar
Test Tube
Test Tube Holder
Test Tube Rack
Thermometer
Volumetric Flask, 500mL
Wash Bottle