1. What is Hydrogen Ion Concentration?

The hydrogen ion concentration [H+] is a measure of the acidity of a solution. It is inversely related to the pH value, with lower pH values corresponding to higher hydrogen ion concentrations.

2. How Does the Calculator Work?

The calculator uses the following formula:

Where:

• \( [H^+] \) — Hydrogen ion concentration in moles per liter (M)
• \( pH \) — The pH value of the solution (0-14 scale)

Explanation: The pH scale is logarithmic, meaning each whole pH value below 7 is ten times more acidic than the next higher value.

3. Importance of pH and [H+]

Details: Hydrogen ion concentration is crucial in chemistry, biology, medicine, and environmental science. It affects enzyme activity, chemical reactions, and biological systems.

4. Using the Calculator

Tips: Enter a pH value between 0 (very acidic) and 14 (very basic). The calculator will determine the corresponding hydrogen ion concentration in molarity (M).

5. Frequently Asked Questions (FAQ)

Q1: What is the [H+] of pure water?
A: Pure water at 25°C has a pH of 7.0, corresponding to [H+] = 1.0 × 10⁻⁷ M.

Q2: How does temperature affect pH and [H+]?
A: The pH of pure water decreases with increasing temperature as the water self-ionization increases, though [H+] = [OH⁻] remains true.

Q3: What's the [H+] in stomach acid?
A: Stomach acid typically has pH 1.5-3.5, corresponding to [H+] ≈ 0.03-0.003 M.

Q4: How accurate is this calculation?
A: This gives the theoretical [H+] for ideal solutions. Real solutions may show slight deviations due to activity coefficients.

Q5: What's the relationship between pH and pOH?
A: In aqueous solutions at 25°C: pH + pOH = 14, where pOH = -log[OH⁻].