Final answer:
The hydroxide ion concentration [OH-] is equal to the base concentration of KOH because KOH completely dissociates in water, with each molecule producing one hydroxide ion.
Step-by-step explanation:
For a strong base like KOH, the relationship between the base concentration and hydroxide ion concentration is straightforward. When KOH dissolves in water, it completely dissociates into potassium ions (K+) and hydroxide ions (OH-).
KOH(s) → K+(aq) + OH-(aq)
Therefore, the hydroxide ion concentration [OH-] is equal to the base concentration of KOH in solution because each molecule of KOH produces one hydroxide ion.
This means that for every mole of KOH that dissolves, one mole of hydroxide ions is produced, implying direct proportionality between the concentration of KOH and the concentration of hydroxide ions.
In solutions of the same concentration, stronger bases ionize to a greater extent, and so yield higher hydroxide ion concentrations than do weaker bases. A stronger base has a larger ionization constant than does a weaker base.