1. What is pH?

pH is a measure of the acidity or basicity of an aqueous solution. It is defined as the negative logarithm (base 10) of the hydronium ion concentration [H₃O⁺]. The pH scale typically ranges from 0 to 14, with lower values indicating acidic solutions and higher values indicating basic solutions.

2. How Does the Calculator Work?

The calculator uses the pH formula:

Where:

• \( [H_3O^+] \) — Hydronium ion concentration (mol/L)
• \( \log \) — Logarithm base 10

Explanation: The formula calculates the negative logarithm of the hydronium ion concentration to determine the pH value of a solution.

3. Importance of pH Calculation

Details: pH measurement is crucial in various fields including chemistry, biology, environmental science, and medicine. It helps determine the acidity or alkalinity of solutions, which affects chemical reactions, biological processes, and environmental conditions.

4. Using the Calculator

Tips: Enter the hydronium ion concentration in moles per liter (mol/L). The value must be greater than 0. The calculator will compute the corresponding pH value.

5. Frequently Asked Questions (FAQ)

Q1: What is the relationship between pH and [H₃O⁺]?
A: pH is inversely related to [H₃O⁺]. As [H₃O⁺] increases, pH decreases, indicating higher acidity.

Q2: What are typical pH values for common substances?
A: Pure water has pH 7 (neutral), lemon juice ~2.0 (acidic), baking soda solution ~8.3 (basic).

Q3: Can pH be negative or greater than 14?
A: Yes, for very concentrated strong acids pH can be negative, and for very concentrated strong bases pH can exceed 14.

Q4: How accurate is this calculation?
A: The calculation provides a theoretical pH value. Actual measurements may vary due to temperature, ionic strength, and other factors.

Q5: What's the difference between [H⁺] and [H₃O⁺]?
A: In aqueous solutions, hydrogen ions immediately form hydronium ions (H₃O⁺) with water molecules. The terms are often used interchangeably in pH calculations.