Answer:
[OH⁻] = 2,6x10⁻¹¹
Acidic
Explanation:
The kw in water is:
2 H₂O(l) ⇄ OH⁻(aq) + H₃O⁺(aq)
kw = [OH⁻] [H₃O⁺] = 1,00x10⁻¹⁴
If concentracion of H₃O⁺ is 3,9x10⁻⁴M:
[OH⁻] [3,9x10⁻⁴M] = 1,00x10⁻¹⁴
<em>[OH⁻] = 2,6x10⁻¹¹</em>
pH is defined as - log[H₃O⁺]. If pH>7,0 the solution is basic, if pH<7,0 solution is acidic, if pH=7,0 solution is neutral.
In this problem,
pH = - log [3,9x10⁻⁴M] = <em>3,4</em>
As pH is < 7.0, the solution is <em>acidic</em>
<em></em>
I hope it helps!
