1. What is [H⁺] Concentration?

The hydrogen ion concentration ([H⁺]) is a measure of the acidity of a solution. It represents the molar concentration of hydrogen ions in a solution and is directly related to both pH and pOH values.

2. How Does the Calculator Work?

The calculator uses the following equations:

Where:

• pOH — The negative logarithm of hydroxide ion concentration (unitless, 0-14 scale)
• pH — The negative logarithm of hydrogen ion concentration (unitless, 0-14 scale)
• [H⁺] — Hydrogen ion concentration in moles per liter (M)

Explanation: The equations show the inverse relationship between pH and pOH in aqueous solutions at 25°C, where pH + pOH = 14.

3. Relationship Between pH, pOH and [H⁺]

Details: In any aqueous solution at 25°C, the sum of pH and pOH equals 14. Knowing either pH or pOH allows calculation of the other, and subsequently the hydrogen ion concentration.

4. Using the Calculator

Tips: Enter the pOH value (between 0 and 14). The calculator will compute the corresponding [H⁺] concentration in molarity (M).

5. Frequently Asked Questions (FAQ)

Q1: What is the range of valid pOH values?
A: pOH values range from 0 (very basic) to 14 (very acidic), mirroring the pH scale but inversely.

Q2: How is [H⁺] related to solution acidity?
A: Higher [H⁺] means more acidic solution. Neutral water at 25°C has [H⁺] = 1×10⁻⁷ M.

Q3: Why is 25°C specified?
A: The pH + pOH = 14 relationship holds at 25°C. At other temperatures, the sum changes slightly due to changes in water's autoionization constant.

Q4: Can I calculate [OH⁻] from this?
A: Yes, [OH⁻] = 10⁻ᵖᴼᴴ, similar to how [H⁺] = 10⁻ᵖᴴ.

Q5: What if my pOH is exactly 7?
A: A pOH of 7 indicates a neutral solution at 25°C, with [H⁺] = 1×10⁻⁷ M and pH = 7.