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For acid/base equilibrium, do we only have to use ice tables to find the concentrations of the acid/base at equilibrium if the acid or base is weak? Why do we not use ICE tables if the acid or base is strong?
We need to use ICE tables for weak acids/bases, because weak acids and bases don't completely dissociate and therefore we cannot just assume the concentration of a weak acid or base. Because strong acids and bases completely dissociate, we do not need to use an ICE table to figure out the concentration if everything is dissociated. Hope this helps!
Since strong acids and bases completely dissociate, we know exactly where all of the initial concentration is going. We use ICE tables with the weak acids and bases because the don't completely dissociate and is difficult to determine where the initial concentration ends up. Using the ICE table allows us to track all of these values.
When we are given a strong acid we know that it is completely dissociated because almost all the HA molecules are deprotonated. This allows us to assume that the molar concentration of H3O+ ions is the same as the initial concentration of the strong acid, so we can just calculate pH without using the ICE table. The same is true for a strong base, so we assume the initial concentration is the same for the OH- ions.
Hi! Since strong acids/bases completely dissociate, we can assume that the concentration of H3O+ ions is equal to the concentration of the strong acid, and similarly we can assume that the concentration of OH- ions is equal to the concentration of the strong base. This is why ice tables are not needed for strong acids/bases. On the other hand, for weak acids/bases, you would have to make an ice table to calculate the [H3O+] / [OH-] because weak acids/bases do not completely dissociate. Hope this helps!
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