Final answer:
To calculate the hydronium ion concentration from the given hydroxide ion concentration, divide the ion product of water, 1.0 x 10-14 M2, by the hydroxide ion concentration. This gives a hydronium ion concentration of 2.0 x 10-12 M.
Step-by-step explanation:
The student's question involves calculating the concentration of hydronium ions ([H3O+]) in a solution when the concentration of hydroxide ions ([OH−]) is known. In aqueous solutions, the product of the concentrations of these ions is always equal to the ion product of water, Kw, which is a constant at a given temperature (for most purposes, we use 25°C where Kw = 1.0 × 10−14 M2).
Using the given hydroxide ion concentration of 5.0 × 10−3 M, the hydronium ion concentration can be calculated using the formula:
[H3O+] = Kw / [OH−] = 1.0 × 10−14 M2 / 5.0 × 10−3 M
Performing the calculation gives us:
[H3O+] = 2.0 × 10−12 M
The solution is quite basic, as the [OH−] is much higher than [H3O+].