Hon Chem - Equilibrium

Equilibrium

When the rate of the forward reaction is the same as the rate of the reverse reaction

Why are Reactions reversible?

The reaction does not go to complete conversion of R→P, they appear to stop

Rate of Reaction…

…depends on concentration of reactants

How does Equilibrium happen?

As the reaction occurs, the rate of the forward reaction goes down, while the reverse reaction’s rate goes up

Chemical Equilibrium

State in which forward & reverse reaction balance each other (bc they take place at equal rates)

Law of Equilibrium

Given a temp, a chemical system may reach a state in which a particular ratio of R & P concentrations hav a constant value

Equilibrium Constant

1. Keq: numerical value of the ratio of P concentrations to R concentrations, which each concentration is raised to the corresponding coefficient

2. Only constant at specified temperature

Keq > 1…

…favors the reactants at equilibrium

Keq < 1…

…favors the products at equilibrium

Equilibrium positions depend…

…upon the initial concentrations of R & P (in Keq equations)

Concentration: add product

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Concentration: add reactant

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Concentration: decrease product

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Concentration: decrease reactant

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