Equilibrium

Question 1

Reversible reactions

Answer 1

• have low activation energy for the forward and reverse reaction
• they do not go through completion as once the products form they react together to form the reactants seen in physical processes like evaporation and condensation.
• if confined to a closed system where energy can leave but not matter, then the forward and reverse reaction compete with each other and prevent the reaction from going in either direction.

Question 2

Physical equilibrium

Answer 2

Open systems allow water vapour (matter) to diffuse into surroundings and leave the system. Once all the water has evaporated and escaped the flask is left to dry.

However in a closed system , the evaporation can still occur but the vapour is unable to escape under these conditions water vapour can condense and revert back to the liquid phase within the flask thus in a closed system evaporation and condensation can both occur.