TOPIC 10: Chemical equilibrium Flashcards
What is a reversible reaction?
A reaction in which the products can react together to form the reactants.
What are the conditions for equilibrium to be present?
- The reaction is reversible
- The reaction occurs in a closed container
What is required to happen for a reversible reaction to be in equilibrium?
There must be both a forward and a backward reaction occurring at the same rate continuously. The concentration of the reactant and product stay constant.
What is the Le Châtelier’s principle?
If the system of equilibrium is disturbed, the equilibrium will shift to oppose this distribution.
How does temperature disturb equilibrium?
Increasing temperature - Equilibrium shifts to the endothermic side in order to use up added energy.
Decreasing temperature - Equilibrium shifts to the exothermic side in order to add energy to the surroundings.
How does pressure disturb equilibrium?
Increasing pressure - Equilibrium shifts to the side with fewer gas molecules.
Decreasing pressure - Equilibrium shifts to the side with more gas molecules.
How does concentration disturb equilibrium? (REACTANTS)
Increasing concentration - Equilibrium shifts to the forward reaction to use up added reactants.
Decreasing concentration - Equilibrium shifts to the backward reaction to add to the lower concentration of reactants.
FOR PRODUCTS IT WILL BE THE OPPOSITE
What does Kc stand for?
Equilibrium constant.
What use does Kc have?
The position of equilibrium is usually described as being to the left or the right but the constant gives it in quantitative data. The bigger the Kc, the closer to the right reaction (forward reaction) it lies.
How are Kc equations laid out and how do you find units from them?
REFER TO UNIT 10 NOTES PAGE 4 FOR ANSWER.
What are the Kc rules?
- If the Kc is 1, both reactants and products are equal so equilibrium is in the middle.
- If Kc > 1, Equilibrium has shifted to the right (forward reaction).
