7. Equilibria Flashcards
What is a reversible reaction?
Reversible reactions are ones where the products can react to reform the original reactants.
What is meant by dynamic equilibrium?
The reactants and products are constantly moving
The rate of the forward reaction is the same as the rate of the backward reaction, and the concentrations of the reactants and products remains constant.
Why is having a closed system important for a reaction?
A closed system is one in which none of the reactants or products escape from the reaction mixture. So in an open system, matter and energy can be lost to surroundings.
What is the basic idea of “Le Chatelier’s principle” ?
It says that if a change is made to a system at dynamic equilibrium, the position of the equilibrium moves to minimize this change.
If there is an increase in concentration what happens to the position of the equilibrium?
Equilibrium shifts to the right to reduce the effect of increase in the concentration of a reactant. There will be more products formed now.
If there is a decrease in concentration what happens to the position of the equilibrium
Equilibrium shifts to the left to reduce the effect of a decrease in reactant.
What happens to the position of equilibrium when there is an increase in pressure?
Equilibrium shifts in the direction that produces the smaller number of molecules of gas to decrease the pressure again.
What happens to the position of equilibrium when there is a decrease in pressure?
The equilibrium shifts in the direction that produces the larger number of molecules of gas to increase the pressure again.
What happens to the position of equilibrium when there is an increase in temperature?
Equilibrium moves in the endothermic direction to reverse the change
What happens to the position of equilibrium when there is a decrease in temperature?
Equilibrium moves in the exothermic direction to reverse the change
What is the factor that affects the composition of equilibria?
Temperature
How much in kPa is 1atm?
1atm = 101kPa
What is done to ensure that there is a successful amount of ammonia formed in the haber process?
- Using an excess of reagents
- Removing ammonia by condensing it to a liquid- this causes the equilibrium to shift to the right to replace the ammonia
What are the conditions in the haber process?
200-300atm
450-509 degrees
Finely divided iron catalyst
What is the equation for the contact process?
Synthesis of sulfuric acid.
2SO2 (g) + O2 (g) ⇌ 2SO3 (g)
Forward reaction is exothermic
