1. What is the pH Formula?

The pH formula calculates the acidity or alkalinity of a solution from the hydrogen ion concentration. It provides a logarithmic measure of the activity of hydrogen ions in a solution.

2. How Does the Calculator Work?

The calculator uses the pH formula:

Where:

• \( [H^+] \) — Hydrogen ion concentration in moles per liter (M)
• \( \log \) — Base-10 logarithm

Explanation: The negative logarithm of the hydrogen ion concentration gives the pH value, which ranges from 0 (very acidic) to 14 (very alkaline), with 7 being neutral.

3. Importance of pH Calculation

Details: pH measurement is crucial in chemistry, biology, medicine, environmental science, and many industrial processes. It affects chemical reactions, biological functions, and water quality.

4. Using the Calculator

Tips: Enter the hydrogen ion concentration in molarity (M). The value must be greater than 0. For pure water at 25°C, [H+] is 1.0 × 10⁻⁷ M, giving pH 7.

5. Frequently Asked Questions (FAQ)

Q1: What is a normal pH for drinking water?
A: The EPA recommends drinking water pH between 6.5 and 8.5. Pure water has pH 7 at 25°C.

Q2: How does temperature affect pH?
A: The pH of pure water changes with temperature as the ionization constant of water changes, though it remains neutral.

Q3: What's the relationship between pH and pOH?
A: pH + pOH = 14 at 25°C. pOH is calculated from hydroxide ion concentration.

Q4: Can pH be negative or greater than 14?
A: Yes, for very strong acids (negative pH) or very strong bases (pH >14), though these are rare in most applications.

Q5: How accurate is this calculation?
A: This gives theoretical pH based on [H+]. Actual measurements may differ slightly due to activity coefficients and other factors.