1. What is Hydrogen Ion Concentration?

The hydrogen ion concentration ([H+]) is a measure of the acidity of a solution. It's inversely related to the hydroxide ion concentration ([OH-]) through the water ion product (Kw). This relationship is fundamental in acid-base chemistry.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

• \( [H^+] \) — Hydrogen ion concentration (M)
• \( K_w \) — Water ion product (1.0 × 10⁻¹⁴ M² at 25°C)
• \( [OH^-] \) — Hydroxide ion concentration (M)

Explanation: The equation shows the inverse relationship between hydrogen and hydroxide ions in aqueous solutions at equilibrium.

3. Importance of [H+] Calculation

Details: Calculating hydrogen ion concentration is essential for determining pH (pH = -log[H+]), understanding acid-base balance, and predicting chemical behavior in solutions.

4. Using the Calculator

Tips: Enter [OH-] in molarity (M) and Kw value (default is 1.0E-14 M² for 25°C). Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical value of Kw?
A: At 25°C, Kw is 1.0 × 10⁻¹⁴ M². It varies with temperature.

Q2: How does [H+] relate to pH?
A: pH is the negative logarithm of [H+]. pH = -log10[H+].

Q3: What if I know pH but need [H+]?
A: [H+] can be calculated from pH as [H+] = 10^(-pH).

Q4: Why is Kw temperature dependent?
A: Water's autoionization is an endothermic process, so Kw increases with temperature.

Q5: What are normal [H+] values in biological systems?
A: In human blood, normal [H+] is about 4.0 × 10⁻⁸ M (pH 7.4).