Chapter 2.4 - Equilibrium position ✓ Flashcards
What happens to the concentration of reactants and products at equilibrium?
They remain constant, but the relative concentrations of reactants and products differ between systems.
Do all systems have the same equilibrium composition?
No, some systems favour a high concentration of products, while others favour reactants.
What is the equilibrium constant (Kc)?
A numerical value representing the concentration of all species in a system at equilibrium.
Write down the general formula for the equilibrium constant expression
(check textbook for answers pg14)
What do the coefficients in a balanced chemical equation represent?
The number of atoms or molecules involved in the reaction.
Which states of matter are included in the equilibrium constant expression?
Only gases (g) and aqueous (aq) species. Solids and liquids are excluded.
What is the only factor that will affect Kc?
Temperature
What does a large Kc value indicate?
The equilibrium favours products.
What does a small Kc value indicate?
The equilibrium favours reactants.
What does a Kc value close to 1 indicate?
A: Both reactants and products are present in significant amounts at equilibrium.
Both reactants and products are present in significant amounts at equilibrium.
When can Kc be calculated?
Only once equilibrium has been reached.
What is the reaction quotient (Qc)?
It measures the relative concentrations of reactants and products at any moment, not just at equilibrium.
Does Qc have a constant value?
No, unlike Kc, Qc varies because it is measured at different points before equilibrium is reached.
What does Qc tell us about a system?
It indicates whether a reaction will proceed forward or backward to reach equilibrium.
What does it mean if Qc = Kc?
The system is at equilibrium.
What does it mean if Qc < Kc?
There are more reactants than products, so the reaction will shift forward to reach equilibrium.
What does it mean if Qc > Kc?
There are more products than reactants, so the reaction will shift backward to reach equilibrium.
