Chemical Equilibria Flashcards
1
Q
What is dynamic equilibrium
A
- a state of dynamic equilibrium is one where rate of forward reaction equals to rate of backward reaction for a reversible reaction such that there is no net change in concentration of reactants and the products
2
Q
What is Le Chatelier’s Principle
A
- states that if a change occurs in one of the conditions (concentration, temperature or pressure) under which a reversible reaction is in dynamic equilibrium, the position of equilibrium shifts so as to minimise that change and to re-establish equilibrium
3
Q
Conditions for Haber process
A
- temperature: 450 degrees Celsius
- pressure: 250 atm
- catalyst: finely divided iron catalyst
4
Q
Choice of temperature for Haber process
A
- forward reaction is exothermic, by Le Chatelier’s Principle the production of NH3 is favoured by a low temperature
- if temperature is too low, rate of reaction will be too slow making process uneconomical
- hence a moderate temperature of 450 is used to obtain a reasonable yield of NH3 in a short time
