Equilibrium is established in a reversible reaction when: the [product] = [reactants] rate of reaction of products = rate of reaction of reactants all the reactants dissolve or dissociate product is no longer produced

the [product] = [reactants]

rate of reaction of products = rate of reaction of reactants

Explanation:

The equilibrium state is a state of rest or motion of system. A chemical equilibrium is dynamic in nature.

These are the conditions for a system to be in equilibrium:

it must be involved in reversible chemical processes no matter the extent of the reversibility. the rate of forward reaction must be equal to that of the backward process. The system is closed i.e energy cannot be exchanged. The free energy change of the system is zeroThere is no change in the concentration of each of the species in equilibrium with respect to time. This implies that concentration is constant. The system offers resistance to any change in any of the factors governing the equilibrium.

Ithink 2 is the correct