What is the hydronium ion concentration of a solution with a poh of 6.90? 6.29 × 10−7 m 6.53 × 10−7 m 7.18 × 10−8 m 7.94 × 10−8 m

D. 7.94 x 10⁻⁸ M

Explanation:

Here's the concepts you need to know to solve this:

So, plug in pOH to find pH (since we want hydronium ion concentration, not hydroxide).

6.90 + pH = 14

pH = 7.10

Now, to reverse a negative log, you use 10⁻ˣ, where x is your pH.

[H⁺] =

[H⁺] = 7.94 x 10⁻⁸ M