reverisble reactions (paper 2) 65 Flashcards
what is the term for when a reversible reaction is balanced
the dynamic equilibrium
what is a closed system
when the concerntrations and conditions do not change for the reaction to take place
what happens in a reversible reaction in a closed system
- the forward and backward reactions occur at the same time
- the concerntration of the reactants and products remain constant
if ΔH is given for a reversible reaction which direction is it always for
the forwards direction
if ΔH is negative what type of reaction is the forwards reaction
exothermic
if ΔH is positive what type of reaction is the forwards reaction
endothermic
if ΔH is negative what type of reaction is the backwards reaction
the opposite of the forwards (which would be exothermic) so it is endothermic
if ΔH is positive what type of reaction is the backwards reaction
the opposite of the forwards (which is endothermic) so it is exothermic
what does the position of equilibrium depend on in a reversible reaction
- pressure
- temperature
what is the benefit of being able to move the position of equilibrium
if you want more of one product then you can manipulate the reaction so more of that product is formed
what is Le Chatelier’s Principle
an equilibrium will acct to oppse any change imposed upon it
what type of conditions do exothermic reactions need
Cool / cold
what type of conditions do endothermic reactions need
hot
if you heat a reversible reaction which direction will be favoured
the endothermic direction as it allows heat to be taken in easily
if you cool a reverisble reaction which direction will be favoured
the exothermic direction as it allows heat to be given out easily
what does increasing the pressure of a reverisble reaction always do
encourage the reaction which produces fewer moles of gas (go from more moles to less moles)
what does decreasing the pressure of a reverisble reaction always do
encourage the reaction which produces more moles of gas (go from less moles to more moles)
what effect do catalysists have on reversible reactions
- increase the rate of the forwards and backwards reaction by the SAME AMOUNTS
- so equilibirum stays in the SAME POSITION
- so they yield does NOT CHANGE it is just achieved more quickly
