1. What is pOH?

Definition: pOH is a measure of the hydroxide ion (OH⁻) concentration in a solution. It's the negative logarithm (base 10) of the hydroxide ion concentration.

Purpose: pOH helps in determining the basicity of a solution and is related to pH in the pH/pOH scale (pH + pOH = 14 at 25°C).

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( pOH \) — Negative log of hydroxyl ion concentration
• \( [OH^-] \) — Concentration of hydroxide ions (mol/L)

Explanation: The calculator takes the hydroxide ion concentration and calculates its negative logarithm (base 10) to determine the pOH value.

3. Importance of pOH Calculation

Details: pOH is important in chemistry for determining solution basicity, calculating pH (since pH + pOH = 14), and understanding acid-base equilibria.

4. Using the Calculator

Tips: Enter the hydroxide ion concentration in mol/L (must be > 0). The calculator will compute the pOH value.

5. Frequently Asked Questions (FAQ)

Q1: What is the relationship between pH and pOH?
A: At 25°C, pH + pOH = 14. This relationship comes from the ion product of water (Kw = 1×10⁻¹⁴).

Q2: What does a high pOH value indicate?
A: A high pOH indicates a low concentration of hydroxide ions (acidic solution), while a low pOH indicates a high concentration (basic solution).

Q3: 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.

Q4: Why do we use logarithmic scale for pOH?
A: The logarithmic scale compresses the wide range of possible concentrations into a more manageable scale (typically 0-14).

Q5: How precise are pOH calculations?
A: pOH values are typically reported to 2 decimal places for most applications, though our calculator shows 4 for precision.