Sometimes the basicity of a solution is reported using pOH (pOH = -log[OH-]). What is the

a. [OH-] if pOH = 1.90
b. [H3O+] if pOH = 12.94
c. pH if pOH = 9.70

And what is your problem?

a. pOH = -log(OH^-). Substitute and solve.
b. Use pH + pOH = pKw = 14 and solve for pH, then use pH = -log(H3O^+).
c. See b. pH + pOH = pKw = 14

To find the answer to these questions, we need to calculate the concentration of hydroxide ions [OH-], concentration of hydronium ions [H3O+], or pH based on the given pOH values. Here's how you can solve each part:

a. [OH-] if pOH = 1.90:
To find [OH-], we can use the formula: [OH-] = 10^(-pOH)
Substituting the given pOH value: [OH-] = 10^(-1.90)
Using a calculator, we find that [OH-] is approximately 0.012589 M.

b. [H3O+] if pOH = 12.94:
To find [H3O+], we need to use the relationship between pOH and pH: pH + pOH = 14
First, let's find the pH value: pH = 14 - pOH
Substituting the given pOH value: pH = 14 - 12.94
Using a calculator, we find that the pH is approximately 1.06.
Now, we can find [H3O+] using the formula: [H3O+] = 10^(-pH)
Substituting the pH value: [H3O+] = 10^(-1.06)
Using a calculator, we find that [H3O+] is approximately 0.079433 M.

c. pH if pOH = 9.70:
Similar to part b, we can use the relationship between pOH and pH: pH + pOH = 14
First, let's find the pH value: pH = 14 - pOH
Substituting the given pOH value: pH = 14 - 9.70
Using a calculator, we find that the pH is approximately 4.30.