1. What is [OH-] Calculation?

The [OH-] calculation determines the hydroxide ion concentration in a solution from its pOH value. This is a fundamental calculation in acid-base chemistry and water analysis.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( [OH^-] \) — Hydroxide ion concentration (moles per liter)
• \( pOH \) — Negative logarithm of hydroxide ion concentration

Explanation: The pOH scale is the negative base-10 logarithm of the hydroxide ion concentration, similar to how pH relates to hydrogen ion concentration.

3. Importance of [OH-] Calculation

Details: Calculating hydroxide ion concentration is essential for understanding basic solutions, determining pH values, and analyzing water quality parameters in various scientific and industrial applications.

4. Using the Calculator

Tips: Enter pOH value between 0 and 14. The calculator will compute the corresponding hydroxide ion concentration in moles per liter (M).

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 hydrogen ion and hydroxide ion concentrations.

Q2: What are typical [OH-] values in water?
A: In neutral water at 25°C, [OH-] = 10⁻⁷ M. Basic solutions have [OH-] > 10⁻⁷ M, while acidic solutions have [OH-] < 10⁻⁷ M.

Q3: How does temperature affect [OH-] calculations?
A: Temperature affects the ion product of water (K_w), which changes the pH+pOH relationship. The standard calculation assumes 25°C.

Q4: Can this calculator be used for concentrated solutions?
A: For highly concentrated solutions, activity coefficients should be considered for accurate calculations, as the simple relationship may not hold.

Q5: What are common applications of [OH-] calculations?
A: Water treatment, pharmaceutical manufacturing, chemical processing, environmental monitoring, and educational laboratories frequently use these calculations.