Classify each as acidic or basic - pH 9 - pH 2.3 - pH 11 - pH 5 - solution where the concentration of hydronium ions [H ] is 0.0056 M - solution where the concentration of hydronium ions [H ] is 3.45 E-9 M.

pH = 9: Basic; pH = 2.3: acidic; pH = 11: basic; pH = 5: Acidic; [H⁺] = 0.0056M: Acidic; [H⁺] = 3.45E-9M: Basic

Explanation:

A solution is defined as acidic when pH < 7 and as basic when pH > 7.

Also, pH = -log[H⁺].

Thus:

pH = 9: >7 → Basic

pH = 2.3: <7 → Acidic

pH = 11: >7 → Basic

pH = 5: <7 → Acidic

[H⁺] = 0.0056M, pH = -log0.0056M = 2.25: <7: Acidic

[H⁺] = 3.45E-9M, pH = 8.46: > 7: Basic

the answer is c i believe