Energy and change, rate and extent of reaction, chemical equilibrium, Flashcards
heat of reaction (ΔH)
The energy absorbed or released in a chemical
reaction.
exothermic
Reactions that release energy
endothermic
Reactions that absorb energy.
activation energy
The minimum energy needed for a reaction to take place
activated complex
the unstable transition state from reactants to products
reaction rate
The change in concentration of reactants or products per unit time.
The collision theory
Is a model that explains reaction rate as the result of particles colliding with a certain minimum energy to form products.
catalyst
A substance that increases the rate of a chemical reaction without itself undergoing a permanent change.
Explain that a catalyst increases the rate of a reaction
By providing an alternative path of lower activation energy. It therefore decreases the net activation energy.
An open system
continuously interacts with its
environment
closed system
is isolated from its surroundings ie container
A reversible reaction
A reaction is reversible when products can be converted back to reactants and vice versa.
Chemical equilibrium
It is a dynamic equilibrium when the rate of the forward
reaction equals the rate of the reverse reaction.
Le Chatelier’s principle
When the equilibrium in a closed system is disturbed, the system will re-instate a new equilibrium by favouring the reaction that will oppose the
disturbance.
