Determine the [H+] when [OH-] is 2.0 times 10^-2 mole.dm-3.
(H^+)(OH^-) = Kw = 1E-14
You know Kw and OH^-; solve for H^+
To determine the concentration of hydrogen ions ([H+]) when the concentration of hydroxide ions ([OH-]) is given, we can use the concept of the ionic product of water (Kw). The ionic product of water is the product of the concentrations of hydrogen ions and hydroxide ions in a water solution, and it is always equal to 1.0 x 10^(-14) at 25 degrees Celsius.
The equation for the ionic product of water is:
Kw = [H+][OH-]
Given that [OH-] is 2.0 x 10^(-2) mole.dm^(-3), we can calculate [H+] by rearranging the equation and substituting the given value:
[H+] = Kw / [OH-]
[H+] = (1.0 x 10^(-14)) / (2.0 x 10^(-2))
Now, let's calculate [H+]:
[H+] = 5.0 x 10^(-13) mole.dm^(-3)
Therefore, the concentration of hydrogen ions [H+] is 5.0 x 10^(-13) mole.dm^(-3) when the concentration of hydroxide ions [OH-] is 2.0 x 10^(-2) mole.dm^(-3).