Equilibrium

What does equilibrium mean?

• reversible reaction is carried out in a closed container so reactants and products cannot escape

• Forward and reverse reaction happen at exact Same speed

What is the Le Chatelier principle?

States that if you change the conditions of a system at equilibrium, the system will Shift in the direction that cancels out or undoes the change to restore balance

What happens at equilibrium when the concentration changes?

1) increase of concentration: it moves the eq position to the other side

2) decrease of c: moves it to the same side (stays)

What happens with pressure in equilibrium?

1) increasing pressure: shifts eq position to the side with the fewest gas molecules (ONLY GAS)

2) decreasing pressure: shifts to side with the fewest gas molecules

Only when reactions involve gases!

What happens with the temperature in equilibrium?

1) Place heat:

• Delta H = + (endothermic) —> heat at reactant

• Delta H = - (exothermic) —> heat at product

2) Shift rule:

• temp increase = switches sides

• temp decrease = stays at same side