Le Chatelier's Principle Classroom Demonstration Kit

Le Chatelier's Principle is a qualitative rule, which allows the prediction of the effect of temperature, pressure and concentration changes on chemical reactions. The principle states: A chemical system at equilibrium whem stressed by external forces will adjust in such a way as to minimize that stress. For example when a system is subjected to increased pressure it adjusts so that it will occupy less volume. This offsets the pressure increase. If ice is placed under an increased pressure, it melts because the water obtained from a given mass of ice occupies less volume. In the formation of ammonia (the Haber process) from hydrogen and nitrogen, the product of the reaction (NH3 occupies less volume than the two uncombined gases. The increase in pressure favors the production of ammonia.

This experiment is divided in to three separate reactions demonstrating how different types of stress effecet equilibrium. Students are asked to predict the outcome of each situation and then prove or disprove their predictions.

Contains:
6 x 25 ml Hydrochloric Acid, 36% Solution
1 x 200 ml Sodium Hydroxide, 0.1N Solution
2 x 25 ml Bromothymol Blue, 0.04% Solution
1 x 25 ml Potassium Thiocyanate Crystals
2 x 200 ml Potassium Thiocyanate, 0.002M
2 x 25 ml Ferric Nitrate, 0.2M Solution
1 x 100 g Sodium Chloride Crystals
1 x 25 g Sodium Phosphate, Dibasic, Heptahydrate

Each bottle of our reagents come standard with an MSDS sheet included. If you require a copy of this prior to purchase, please contact us.