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 hydrogen ion concentration. The pH scale ranges from 0 to 14, with 7 being neutral, values below 7 acidic, and values above 7 basic.

2. How Does the Calculator Work?

The calculator uses the pH formula:

Where:

• \( pH \) — pH value (dimensionless)
• \( [H^+] \) — Hydrogen ion concentration (mol/L)
• \( \log \) — Base-10 logarithm

Explanation: The formula calculates the negative logarithm of the hydrogen ion concentration to determine the acidity or basicity of a solution.

3. Importance of pH Calculation

Details: pH measurement is crucial in various fields including chemistry, biology, environmental science, medicine, and industry. It helps determine chemical reactivity, biological function, water quality, and many other important parameters.

4. Using the Calculator

Tips: Enter the hydrogen 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 [H⁺]?
A: pH is inversely related to hydrogen ion concentration. As [H⁺] 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), and bleach ~12.5 (highly basic).

Q3: How does temperature affect pH?
A: The pH of pure water decreases with increasing temperature due to changes in water's autoionization constant, though the solution remains neutral.

Q4: Can pH be negative or greater than 14?
A: Yes, for extremely concentrated acids (pH < 0) or bases (pH > 14), though such solutions are rare and require special handling.

Q5: How is pH measured experimentally?
A: pH is typically measured using pH meters with glass electrodes, pH paper (litmus paper), or pH indicators that change color at specific pH values.