1. What is pOH and [OH^-]?

The pOH scale measures the hydroxide ion concentration in a solution, just as pH measures hydrogen ion concentration. [OH^-] represents the actual molar concentration of hydroxide ions in solution.

2. How Does the Calculator Work?

The calculator uses the fundamental relationship:

Where:

• \( [OH^-] \) — Hydroxide ion concentration (mol/L)
• \( pOH \) — Negative logarithm of hydroxide ion concentration

Explanation: This logarithmic relationship means each unit change in pOH corresponds to a tenfold change in hydroxide ion concentration.

3. Importance of [OH^-] Calculation

Details: Knowing hydroxide ion concentration is essential for understanding solution basicity, chemical equilibrium calculations, and many biochemical processes.

4. Using the Calculator

Tips: Enter pOH value between 0 and 14. The calculator will provide the hydroxide ion concentration in both decimal and scientific notation.

5. Frequently Asked Questions (FAQ)

Q1: What's the relationship between pH and pOH?
A: In aqueous solutions at 25°C: pH + pOH = 14. This relationship allows conversion between pH and pOH.

Q2: What are typical pOH values for common solutions?
A: Pure water has pOH = 7, acidic solutions have pOH > 7, and basic solutions have pOH < 7.

Q3: Why use pOH instead of just [OH^-]?
A: The logarithmic pOH scale makes it easier to work with the wide range of concentrations encountered in chemistry.

Q4: How precise should my pOH measurement be?
A: For most applications, 2 decimal places is sufficient. High-precision work may require more digits.

Q5: Does temperature affect pOH calculations?
A: Yes, the pH/pOH relationship changes slightly with temperature as the ionic product of water (Kw) changes.