The correct statement is:
A solution of potassium hydroxide will always have more OH ions than a solution of ammonia.
Here's why:
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Potassium hydroxide (KOH) is a strong base that completely dissociates in water to give potassium ions (K⁺) and hydroxide ions (OH⁻). Therefore, in a KOH solution, the concentration of OH⁻ ions is equal to the concentration of KOH.
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Ammonia (NH₃) is a weak base that does not completely dissociate in water. It partially reacts with water to form ammonium ions (NH₄⁺) and hydroxide ions (OH⁻), but the concentration of OH⁻ ions in an ammonia solution is significantly lower than that in a strong base like KOH at the same concentration.
Thus, for a given concentration, KOH will always have a higher concentration of OH⁻ ions compared to ammonia.
Regarding the other statements:
- Conductivity: A solution of KOH will generally have greater conductivity than ammonia due to the higher concentration of ions.
- pH: KOH will have a higher pH, but this is dependent on the concentration of the solutions being compared.
- Concentration of solute: This is not necessarily true as concentrations can vary (the concentration of KOH could be equal to or less than that of ammonia based on solution preparation).
Thus, the most universally correct statement is concerning the number of OH⁻ ions: A solution of potassium hydroxide will always have more OH ions than a solution of ammonia.