1. What are pOH and pH?

pOH and pH are measures of the alkalinity and acidity of a solution, respectively. They are related through the equation: pH + pOH = 14 (at 25°C). pOH is calculated from the hydroxide ion concentration [OH⁻], while pH can be derived from pOH.

2. How Does the Calculator Work?

The calculator uses the following equations:

Where:

• \( [OH^-] \) — Hydroxide ion concentration in moles per liter (M)
• \( pOH \) — Measure of hydroxide ion activity (unitless)
• \( pH \) — Measure of hydrogen ion activity (unitless)

Explanation: The negative logarithm (base 10) of the hydroxide ion concentration gives the pOH, which can then be used to calculate pH.

3. Importance of pOH and pH Calculation

Details: These calculations are essential in chemistry, biology, medicine, and environmental science for understanding solution properties, chemical reactions, and biological systems.

4. Using the Calculator

Tips: Enter the hydroxide ion concentration in molarity (M). The value must be between 1×10⁻¹⁴ and 1 M. The calculator will compute both pOH and pH.

5. Frequently Asked Questions (FAQ)

Q1: What is the relationship between pOH and pH?
A: They are inversely related and always add up to 14 in aqueous solutions at 25°C (pH + pOH = 14).

Q2: What does a high pOH value indicate?
A: A high pOH indicates low hydroxide ion concentration and acidic conditions (low pH).

Q3: What are typical pOH values for common substances?
A: Pure water has pOH 7, bleach ~1, lemon juice ~13, etc.

Q4: Does temperature affect these calculations?
A: Yes, the pH + pOH = pKw relationship changes with temperature as the water ionization constant (Kw) changes.

Q5: Can I calculate [OH⁻] from pH?
A: Yes, first calculate pOH (14 - pH), then [OH⁻] = 10^(-pOH).