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pOH Calculator

Calculate pOH from OH⁻ concentration and convert between pH and pOH.

⚗️ pOH Calculator

⚠ Enter a valid positive value.
Formula
pOH = −log[OH⁻]
pOH Value
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pOH

⚗️ pOH Formula

pOH = −log₁₀[OH⁻]
pH + pOH = 14  (at 25°C)

pOH measures the basicity of a solution through hydroxide ion (OH⁻) concentration. The lower the pOH, the more basic the solution.

📖 Example

✅ [OH⁻] = 0.01 mol/L

pOH = −log(0.01) = −log(10⁻²) = 2

pH = 14 − 2 = 12 (Strongly Basic)

❓ FAQ

What is pOH?
pOH is the negative log of hydroxide ion concentration. Low pOH = basic, high pOH = acidic. pH + pOH = 14 at 25°C.
What is the pOH of pure water?
Pure water has pOH = 7, since [OH⁻] = 10⁻⁷ mol/L and pH = pOH = 7.

🔗 Related

⚗️ pH Calculator ⚗️ pKa Calculator ⚗️ Buffer pH ⚗️ Henderson-Hasselbalch
Comprehensive Guide

Mastering pOH Calculations

Our free pOH Calculator simplifies complex chemistry mathematics, providing step-by-step clarity for analytical problem solving. Whether you're prepping for an AP Chemistry exam or working in a research lab, computing pOH quickly prevents cascading mathematical errors. Mastering the concepts behind pOH is crucial for understanding advanced chemical reactions and laboratory procedures.

Why is pOH Important?

In analytical chemistry, precision is everything. Having a reliable way to compute pOH saves time, prevents wasted materials, and ensures scientific accuracy.

⚡
Speed
Instant
🎯
Accuracy
100%
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Level
All Levels

Always verify your input units before calculating. Mismatched units (e.g., using mL instead of L) are the most common source of error when determining pOH!

Common Applications

  • Academic Study: Speeding up repetitive calculations.
  • Laboratory Practice: Ensuring exact stoichiometry for reactions.
  • Data Validation: Studying for college-level chemistry tests.

Relying solely on the calculator without understanding the underlying formula. Always review the step-by-step breakdown to internalize the mechanics.