1.6 Chemical Equilibria Flashcards
What is dynamic equilibrium?
When the rate of the forward reaction is equal to the rate of the reverse
Give an essential condition for an equilibrium
- Must be in a closed system to be considered an equilibrium reaction
What is Le Chetaliers Principle?
If a change is imposed on a reaction, the reaction will move in the direction of whatever best opposes the change
In the equation
CH4 + H2O == CO + 3H
ΔH°= +210 kJ mol-1
What effect would increasing the temperature have on the position of equilibrium?
The reaction shifts to the right due to the forward reaction being endothermic ( Yield of H increases)
In the equation:
CH4(g) + H2O(g) ⇌ CO(g) + 3H2(g)
ΔH°= +210 kJ mol-1
What effect would increasing the pressure have on the position of equilibrium?
- The reaction would shift to the left
- This is because the forward reaction produces more moles of gas than the reverse
What effect does a catalyst have on the position of equilibrium?
None
Why does a catalyst have no effect on the position of equiibrium?
Because it effects the rates of the forward reaction and backward reaction equally
What condition affects the equilibrium constant?
Temperature
What are the units for the equilibrium constant?
mol-1dm-3
What type of system is equilibrium constant relevant for?
Homogeneous systems in equilibrium
What does the equilibrium constant being greater or lesser than 1 suggest for the position of equilibrium?
- Greater than 1 = over to the right
- Less than 1 = over to the left
What effect does decreasing the temperature in an endothermic reaction have on Kc?
Kc decreases
What effect does increasing the temperature in an endothermic reaction have on Kc?
Kc increases
What effect does decreasing the temperature in an endothermic reaction have on Kc?
Kc increases
What effect does increasing the temperature in an exothermic reaction have on Kc?
Kc decreases
