equilibrium for dummies Flashcards
what are the Two features of Dynamic Equilibrium
- Forward and backward reactions are occurring at
equal rates. - The concentrations of reactants and products
stays constant
why does equilibrium only happen in a closed system
a beaker may be a closed system for
a reaction that takes place in a solvent, as long as the reactants, products, and solvent do not evaporate.
macroscopic qualities of equilibrium
if macroscopic qualities do not change during time. this includes density state of matter colour and pressure.
reversible reaction
when a equilibrium reaction is not in a closed container.
what does dynamic mean
both backwards and forwards reaction happen simultaneously
‘position of equilibrium’
the composition of the equilibrium mixture.
‘position of equilibrium’ example
If the position of equilibrium favours the reactants (also
described as “towards the left”) then the equilibrium
mixture will contain mostly reactants.
Le Chatelier’s Principle
Le Chatelier’s principle states that if an external
condition is changed the equilibrium will shift to
oppose the change (and try to reverse it).
whta happens if the temperature increases
If temperature is increased the equilibrium will
shift to oppose this and move in the endothermic
direction to try to reduce the temperature by
absorbing heat.
what happens if the temperature decreases
If temperature is decreased the equilibrium will
shift to oppose this and move in the exothermic
direction to try to increase the temperature by
giving out heat.
what happens if pressure increases
Increasing pressure will cause the equilibrium to shift
towards the side with fewer moles of gas to oppose the
change and thereby reduce the pressure.
what happens if pressure decreases
Decreasing pressure will cause the equilibrium to shift
towards the side with more moles of gas to oppose the
change and thereby increase the pressure.
what happens when the moles are the same
If the number of moles of gas is the same on both sides of
the equation then changing pressure will have no effect on
the position of equilibrium
what happens to equilibrium in a presents of a catalyst
the reaction forwards and backwards will speed up and equilibrium is reached quicker. catalyst does not affect equilbrium.
what does increasing concentration of OH ions have on equilbrium
Increasing the concentration OH- ions causes the equilibrium to shift to oppose this
and move in the forward direction to remove and decrease the concentration of OH- ions. The position of equilibrium will shift towards the right, giving a higher yield of I- and IO-. ( The colour would change from brown to colourless)
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