Final answer:
The question regarding the number of hydroxide ions cannot be answered without additional information such as the molarity of hydroxide ions in the solution. Once the molarity is known, the number of ions can be calculated by multiplying the molarity by Avogadro's number.
Step-by-step explanation:
The student has asked about the quantity of individual hydroxide ions in a solution, but the question appears to be incomplete or missing needed context such as concentration in molarity (M) or amount of substance in moles. Typically, in chemistry, one would calculate the number of hydroxide ions in a solution by using the concentration provided ([OH-]) and Avogadro's number (6.022 × 1023 ions/mol).
In order to determine hydroxide ion concentration, it's critical to understand the relationship between hydronium ions ([H3O+]) and hydroxide ions ([OH-]) in an aqueous solution. This is because the product of [H3O+] and [OH-] concentrations at a given temperature is always constant and equal to the ion product of water (Kw). For example, if we know that [H3O+] is 9.5 × 10-8 M, we can calculate [OH-] using the expression Kw = [H3O+][OH-] where, at 25 °C, Kw is 1.0 × 10-14.
To provide a specific number of hydroxide ions, the concentration of [OH-] in molarity would be needed. For example, if the [OH-] were 1.3 × 10-6 M, the number of hydroxide ions would be calculated as (1.3 × 10-6 mol/L) × (6.022 × 1023 ions/mol) = 7.83 × 1017 ions.