What is the [OH-] of a solution of baking soda with a pH of 8.5

To calculate the hydroxide ion concentration ([OH-]) in a solution with a pH of 8.5, we can use the formula:

pH = -log[H+]

Since water has a pH of 7 (neutral), we know that in a basic solution (pH > 7), [OH-] is greater than [H+]. Therefore, we can use the formula:

pH + pOH = 14

From this formula, we can calculate the pOH of the solution:

pOH = 14 - pH
pOH = 14 - 8.5
pOH = 5.5

Now, we can calculate the [OH-] concentration using the formula:

[OH-] = 10^(-pOH)
[OH-] = 10^(-5.5)
[OH-] = 3.16 x 10^(-6) M

Therefore, the [OH-] concentration of a solution with a pH of 8.5 is 3.16 x 10^(-6) M.