Question

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

Answer 1

Answer:

D. 7.94 x 10⁻⁸ M

Explanation:

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

• [H⁺] = hydronium ion concentration, [OH⁻] = hydroxide concentration

• p is the negative log of something, so pOH = -log[OH⁻]

• pOH + pH = 14

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⁺] = $10^{-7.10}$

[H⁺] = 7.94 x 10⁻⁸ M

Answer 2

Answer:

7.94 x 10^-8 M

Explanation: