6.2- CHANGING THE CONDITIONS OF AN EQUILIBRIUM REACTION Flashcards
What would reversible reactions in a closed system produce?
equilibrium mixtures containing both products + reactants
Examples of industrial processes that have reversible reactions as a key step?
production of ammonia or sulfuric acid
If the proportion of products in equilibrium mixture increased, where does equilibrium move?
equilibrium moves to right, or in forward direction
If the proportion of reactants in equilibrium mixture increased, where does equilibrium move?
equilibrium moves to right, or in forward direction
How can you move the equilibrium position to the left or right?
by varying conditions i.e. temp, concentration of species involved, or pressure (in cases of reactions involving gases)
What does Le Chatelier’s principle state?
if system at equilibrium disturbed, equilibrium moves in direction that tends to reduce disturbance
If any factor is changed which affects the equilibrium mixture, what will the position of equilibrium change to do?
position of equilibrium will shift as to oppose the change
What does Le Chatelier’s principle not tell us and so what can we not predict?
does not tell us how far the equilibrium moves so cannot predict the quantities involved
What does Le Chatelier’s principle say if you increase the concentration of one of the reactants?
equilibrium will shift in direction that tends to reduce concentration of this reactant
What do you end up with if you increase the concentration of one of the reactants?
end up with greater proportion of products in reaction mixture
What would happen if you remove C as it forms? A + B = C + D
equilibrium would move to right to produce more C (+ D) using up A + B
When do pressure changes affect a reaction?
only affect reactions involving gases
What will changing the overall pressure change?
will only change position of equilibrium of gaseous reaction if there are a different number of molecules on either side of reaction
What does increasing the pressure of a gas mean?
there are more molecules of it in given volume
What is equivalent to increasing the pressure but for solution?
increasing conc. of solution
What affect does pressure have if there is the same number of moles of gases on both sides of the equation?
pressure has no effect on equilibrium position
If one direction of a reversible reaction is exothermic, what is the other side like?
endothermic
What is the size of enthalpy like on both sides of a reversible reaction?
size of enthalpy same in both directions but signs change
What happens if you increase the temperature of equilibrium mixture that’s exothermic in forward reaction?
equilibrium mixture will contains greater proportion of reactants
Do catalysts have an effect on the position of equilibrium?
no
What do catalysts work by doing?
work by producing alternative route for reaction, which has lower activation energy of reaction
Which direction of a reversible reaction does a catalyst affect?
affects forward + back reactions equally
What do catalysts allow equilibrium to do?
allow equilibrium to be reached more quickly + so important in industry
