1. What is Hydroxide Ion Concentration?

The hydroxide ion concentration ([OH⁻]) is a measure of the amount of hydroxide ions in a solution. It's directly related to the pOH of the solution and is important in determining the basicity of a solution.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The pOH scale is inversely related to hydroxide ion concentration - as pOH increases, [OH⁻] decreases exponentially.

3. Importance of [OH⁻] Calculation

Details: Knowing hydroxide ion concentration is essential for understanding solution basicity, calculating pH, and in various chemical and biological processes.

4. Using the Calculator

Tips: Enter pOH value between 0 and 14. The calculator will compute the corresponding hydroxide ion concentration in mol/L.

5. Frequently Asked Questions (FAQ)

Q1: What is 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 [OH⁻] values?
A: Neutral water at 25°C has [OH⁻] = 1×10⁻⁷ mol/L. Basic solutions have higher [OH⁻], acidic solutions have lower.

Q3: How does temperature affect [OH⁻]?
A: The autoionization of water (and thus [OH⁻]) is temperature dependent. The pH + pOH relationship changes with temperature.

Q4: Can [OH⁻] be measured directly?
A: While pH/pOH can be measured with indicators or meters, [OH⁻] is typically calculated from pOH measurements.

Q5: What's the difference between [OH⁻] and alkalinity?
A: [OH⁻] measures free hydroxide ions, while alkalinity measures a solution's capacity to neutralize acids, including other bases besides OH⁻.