Final answer:
Chemical equilibrium is when forward and reverse reactions occur at equal rates, with no net concentration change over time. Equilibrium may not be reached if conditions are not stable or the system is disturbed. Economic equilibrium refers to a balance between expenditures and output, and a national income of $300 not at equilibrium suggests a disparity between these elements.
Step-by-step explanation:
Equilibrium is a concept in Chemistry referring to the state where the rates of the forward and reverse reactions are equal, resulting in no net change in the concentration of reactants and products over time. It is a dynamic process where reactions continue to occur, but the overall concentrations remain constant. This does not imply that the amounts of reactants and products are the same, but rather that their rates of formation and depletion are balanced.
A reason equilibrium might not be reached in a chemical system could be due to changes in conditions such as temperature, pressure, or concentration, which shift the rates of the forward and reverse reactions. For instance, if a reactant is continually added or a product is removed, the system may not reach equilibrium. If the chemical reaction is not given enough time or the conditions are not right, the equilibrium might not be established, and the reaction can favor either the reactants or products disproportionately.
When applying equilibrium to economic models, as implied by the mention of a national income of $300 not being at equilibrium, it means that the economic activities (expenditures and output) are not balanced. This could be due to various factors such as government spending, consumer behavior, or external economic shocks, which cause a discrepancy between what is produced and what is consumed, leading to disequilibrium in the economy.