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Article: Equilibrium
- Article from:
- Chemistry: Foundations and Applications
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Equilibrium
A state of equilibrium exists in a process when the rate of the forward process equals the rate of the reverse process. The equilibrium condition exists in relation to thermal, mechanical, and chemical changes. For example, within a closed flask, liquid water evaporates to form vapor, and at the same time the vapor condenses to form liquid. When the rate of evaporation equals the rate of condensation, the system is said to be in a state of equilibrium:
A state of thermal equilibrium exists when the heat loss of a system is equal to the heat gain. Chemical equilibrium exists when a reversible chemical reaction occurs within a closed system, such as a sealed flask, and the ...