Mod 5 EQUILIBRIUM AND ACID REACTIONS: Factors that affect equilibrium Flashcards
Inquiry question: What factors affect equilibrium and how?
Identify Le Chatelier’s Principle.
Le Chatelier’s Principle states that a system in equilibrium subjected to change will strive to regain a new state of equilibrium by countering the change
Identify what will happen to equilibrium if heat is added (increasing temperature).
Equilibrium will favour the endothermic side
Identify what will happen to equilibrium if heat is removed (decreasing temperature).
Equilibrium will favour the exothermic reaction
Identify the type of reaction of Cobalt(II) Chloride Hydrate (CoCl2·H2O)
Heat is a reactant, hence this is an endothermic reaction (energy is absorbed)
Describe an endothermic reaction.
Endothermic reactions absorb energy typically in the form of heat, as heat is a reactant and is absorbed from the surroundings.
What happens when the concentration of reactants is increased in a chemical reaction?
If the concentration of reactants is increased, the system will regain a new equilibrium position by favouring the forward reaction (products).
Identify the result of increased concentration of products in terms of equilibrium
The system will regain a new equilibrium position, favouring reactants.
In the reaction of Iron(III) Thiocyanate:
Fe3+(aq)+SCN−(aq)⟷Fe(SCN)2+(aq)
If extra Fe+ is added, the system would favour…
Forward reaction. More products would need to be produced to reach the equilibrium state.
In the reaction of Iron(III) Thiocyanate:
Fe3+(aq)+SCN−(aq)⟷Fe(SCN)2+(aq)
If extra Fe(SCN)2+ is added, the system would favour…
Reverse reaction. More reactants would need to be produced to reach the new equilibrium state.
Describe the relationship between pressure and volume
Inverse. If pressure increases in a reaction, volume must decrease. If pressure decreases in a reaction, volume must increase.
Describe the effect of changing pressure on the number of gaseous molecules in a reaction.
Increasing pressure favours the reaction producing fewer gaseous molecules, while decreasing the pressure favours the reaction producing more gaseous molecules.
What is the system’s reaction when the pressure is increased in the context of the interaction between nitrogen dioxide and dinitrogen tetroxide.
N2O4(g) <–> 2NO2(g)
Equilibrium shift to the left (least amount of gaseous molecules)
Describe the rate of the forward reaction in terms of the collision theory.
Concentration of reactants decreases overtime. This leads to a decrease in the number of reactant particles. Fewer particles mean fewer collisions happening, slowing down the rate of the forward reaction.
Describe the rate of the reverse reaction in terms of the collision theory.
Concentration of product particles increases, thus increasing the number of successful collisions happening, rate of the reverse reaction increases.
What happens when equilibrium is established in a reaction?
Forward and reverse reactions will still occur due to the collision between molecules, with no changes in concentration are observed.
