topic 10 -Chemical equilibria Flashcards
What is a reversible reaction?
A reversible reaction is one which can be made to go in either direction depending on the conditions
What is a closed system?
A closed system is a physical system where no chemical/matter can enter or exist.
Energy can however be transferred in and out at will
What is dynamic equilibrium?
In a closed system when the rate of the forward reaction is equal to the rate of the reverse reaction and the concentration of the reactants and products remain constant the reaction has reached a POSITION OF EQUILIBRIUM
What happens to the rate of the forward reaction as the reaction goes on?
At the beginning of the reaction the concentration of the reactants were at their maximum. This means the rate of reaction was at its fastest.
As the reactants react their concentration fall. This means they are less likely to collide and react and so the rate of the forward reaction falls as time goes on.
What is LE CHATELIER’S principle?
If a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to counteract change.
What happens to the position of equilibrium if you increase the concentration of reactants?
The PoE will moves to the right (forward direction) if you increase the concentration of a reactant.
What happens if you decreased the concentration of reactants?
It will move left in the direction of the reactants.
Why does the Position of equilibrium change when you increase the pressure?
Pressure is caused by gas molecules hitting the sides of their container. The more molecules you have in the container, the higher the pressure will be. The system can reduce the pressure by reacting in such a way as to produce fewer molecules.
What happens to the position of equilibrium when you increase the pressure?
Increasing the pressure on a gas reaction shifts the position of equilibrium towards the side with fewer molecules.
What is homogenous system?
- is one which all components are in the same phase.
what is a heterogenous system?
- is where at least 2 different phases are present.
what is the haber process?
-ammonia is manufactured in industry by direct synthesis of nitrogen and hydrogen.
why are the conditions of 450° and 250 atm used in the haber process?
- very strong nitrogen bond producing a high activation energy.
- iron is used as a catalyst industrially as it is cheaper than the othe rmetal that can also act as a cataylst.
- catalyst also doesn’t function efficiently at low temperatures.
what is the contact process?
- sulfuric acid is manufactured
- sulfur dioxide + oxygen at the surface of a solid vanadium (V) oxide catalyst to form sulfur trioxide
