Virtual Lab: Le Chatelier's Principle Inquiry
BACKGROUND: Equilibrium exists when the rates of the forward and reverse reactions are equal. When a stress is added to the reaction, the rates are no longer equal. The reaction will proceed in such a way to make the rates back to equal and establish a new equilibrium. This is known as LeChatelier’s principle.
PURPOSE: Observe stress on reactions and record the shift that the reaction undergoes to relieve the stress.
PRE LAB:
- Define Equilibrium.
- When a system is at equilibrium, are the concentrations equal or constant?
PROCEDURE:
For each experiment, click to see the effect of various stressors on equilibrium and record your observations. Then analyze your results and complete the conclusion questions.
|
EXPERIMENT 1:
|
|
Click to add HCl (increase the H+ concentration) then add NaOH (decrease the H+ concentration)
Increasing the H+ concentration shifted the reaction to the ______________________
Decreasing the H+ concentration shifted the reaction to the _____________________
Increasing the H+ concentration shifted the reaction to the ______________________
Decreasing the H+ concentration shifted the reaction to the _____________________
|
EXPERIMENT 2:
|
|
Click to add KSCN (increase SCN- concentration)
Click to add Fe(NO3)3 (increase Fe+3 concentration)
Click to add Na2HPO4 (decrease Fe+3 concentration)
Increasing the SCN- concentration shifted the reaction to the _______________________
Increasing the Fe+3 concentration shifted the reaction to the _______________________
Decreasing the Fe+3 concentration shifted the reaction to the ______________________
Click to add Fe(NO3)3 (increase Fe+3 concentration)
Click to add Na2HPO4 (decrease Fe+3 concentration)
Increasing the SCN- concentration shifted the reaction to the _______________________
Increasing the Fe+3 concentration shifted the reaction to the _______________________
Decreasing the Fe+3 concentration shifted the reaction to the ______________________
|
EXPERIMENT 3:
|
|
Click to add 12M HCl (increase Cl- concentration)
Click to add AgNO3 (decrease Cl- concentration)
Increasing the Cl- concentration shifted the reaction to the ____________________
Decreasing the Cl- concentration shifted the reaction to the ____________________
Click to add AgNO3 (decrease Cl- concentration)
Increasing the Cl- concentration shifted the reaction to the ____________________
Decreasing the Cl- concentration shifted the reaction to the ____________________
|
EXPERIMENT 4:
|
|
Click to place test tube in hot water bath. (increase heat)
Click to place test tube on ice. (decrease heat)
Increasing the heat shifted the reaction to the ____________________
Decreasing the heat shifted the reaction to the ___________________
Click to place test tube on ice. (decrease heat)
Increasing the heat shifted the reaction to the ____________________
Decreasing the heat shifted the reaction to the ___________________
|
EXPERIMENT 5:
|
|
Click to place test tube in a hot water bath. (increase heat)
Click to place test tube on ice. (decrease heat)
Increasing the heat shifted the reaction to the ____________________
Decreasing the heat shifted the reaction to the ___________________
Click to place test tube on ice. (decrease heat)
Increasing the heat shifted the reaction to the ____________________
Decreasing the heat shifted the reaction to the ___________________
CONCLUSION:
Upon analyzing your results:
Upon analyzing your results:
- When the concentration of a substance was increased, equilibrium shifted away or towards that side of the reaction?
- When the concentration of a substance was decreased, equilibrium shifted away or towards that side of the reaction?
- When the temperature was increased, equilibrium shifted away or towards the side of the reaction that contains the heat?
- When the temperature was decreased, equilibrium shifted away or towards the side of the reaction that contains the heat?
