When Keq is sufficiently small, this is an okay approximation. The quadratic is best though. Equilibrium Tutorial. Le Chatelier's Principle A chemical system, once it as equilibrium will respond to a stress or change in the environment by responding to reduce the stress.
A complete set of notes including familiar examples. Le Chatelier's Principle notes. Weak acids and weak bases on the other hand like to stay together as molecules, they don't disassociate very much. The measure of how "strong" an acid is is given by Ka. The measure of how "strong" a base is is given by Kb. More hydronium means you have a "stronger" acid. Also remember, square brackets mean concentration in molarity. Sample Problem If Ka is 3. The Solubility Product: Ksp. Ksp comes from Keq, only this time our reactants are solid so they get left out.
That is because for a solid concentration is meaningless. Steps in solving problems 1. Write a balance dissolving equation. Write a Ksp expression no numbers yet. Hence this equilibrium also lies to the left:. All acid—base equilibria favor the side with the weaker acid and base.
Thus the proton is bound to the stronger base. Two species that differ by only a proton constitute a conjugate acid—base pair. For an aqueous solution of a weak acid, the dissociation constant is called the acid ionization constant Ka. Similarly, the equilibrium constant for the reaction of a weak base with water is the base ionization constant Kb.
Acid—base reactions always proceed in the direction that produces the weaker acid—base pair. For example, if there is a salt ion in the solution in addition to the ions present in the solid, then we call it an uncommon ion, and it can increase the value of Ksp. Keq stands for equilibrium constant. The equilibrium constant is the ratio between the concentrations of products and the concentrations of reactants at equilibrium.
This term is only applicable to reactions that are in equilibrium. The reaction quotient and equilibrium constant are the same for reactions that are in equilibrium. We can give the equilibrium constant as the concentrations raised to the power of stoichiometric coefficients. The equilibrium constant is dependent on the temperature of the system considered since the temperature affects the solubility of components and the volume expansion.
However, the equation for the equilibrium constant does not include any details about solids that are among the reactants or the products. Only substances in the liquid phase and gaseous phase are considered.
For example, let us consider the equilibrium between carbonic acid and bicarbonate ion. Ksp is a type of Keq.
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