Chapter 2 - Chemical equilibrium Flashcards
What makes a reaction reversible?
It reversible due to its LOW activation energy both the forwards and reverse reaction
Define dynamic equilibrium
Dynamic equilibrium is when the forward and reverse processes occur at the same rate, resulting in no observable change in the system
What does the equilibrium constant (Kc) show?
It shows a numerical value expressing the relationship between products and reactants of a reaction at equilibrium
What species state can be included in the equilibrium equation?
Only (aq) and (g) species
What does a large values of Kc imply?
It implies that the equilibrium favours the products
What does a small value of Kc imply?
I implies that the equilibrium favours the reactants
What does a value of Kc imply when it is close to 1?
It imply that both reactants and products are present at equilibrium (no neither the products nor reactants are favoured)
What does the reaction quotient (Qc) represent?
It represents the ratio of products to reactants at any given point in a reaction, not necessarily at equilibrium
What imposed changes will affect an equilibrium system?
-Temperature
-Concentration of any one species
-Total pressure in a gaseous system
What does Le Chatelier’s principle state?
It states, “If a system is at equilibrium and a change in conditions is imposed on the system then the system will readjust to establish a new equilibrium that partially counteracts the imposed challenges”
Define collision theory
It is a principle used to predict the rates of chemical reactions.
What happens in an equilibrium reaction if the pressure is increased?
It will favour the side with the fewer moles of gas
What happens in an equilibrium reaction if the pressure is decreased?
It will favour the side with the higher moles of gas
What happens if temperature of an equilibrium system is raised?
It will favour the endothermic process
What happens if temperature of an equilibrium system is lowered?
It will favour the exothermic process
If heat is written in the products side, is it endothermic or exothermic?
Exothermic
If heat is written in the reactants side, is it endothermic or exothermic?
Endothermic
In an equilibrium system when temperature is raised in an endothermic reaction which side is favoured?
Raising the temperature in an endothermic reaction will favour the forward direction because the system will absorb the added heat by shifting to the side that consumes energy
In an equilibrium system when temperature is raised in an exothermic reaction which side is favoured?
Raising the temperature of an exothermic reaction will favour the reverse direction because the system counteracts the change by producing more heat
If the enthalpy change is positive is it exothermic or endothermic?
Endothermic
If the enthalpy change is negative is it exothermic or endothermic?
Exothermic
What happens to an equilibrium system when a catalyst is added?
It will speed up both the forward and reverse reaction of the equilibrium system
