1. What are pH and pOH?

pH and pOH are measures of acidity and alkalinity of a solution. pH represents the negative logarithm of hydrogen ion concentration, while pOH represents the negative logarithm of hydroxide ion concentration. They are related by the equation: pH + pOH = 14 at 25°C.

2. How Does the Calculator Work?

The calculator uses the following formulas:

Where:

• \( [H^+] \) — Hydrogen ion concentration in mol/L
• \( [OH^-] \) — Hydroxide ion concentration in mol/L
• \( \log \) — Base-10 logarithm

Explanation: Enter either hydrogen ion concentration or hydroxide ion concentration, and the calculator will compute all related values using the relationships between pH, pOH, and ion concentrations.

3. Importance of pH Calculation

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

4. Using the Calculator

Tips: Enter either hydrogen ion concentration or hydroxide ion concentration in mol/L. The calculator will automatically compute the complementary values. Values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the relationship between pH and pOH?
A: pH and pOH are related by the equation: pH + pOH = 14 at 25°C in aqueous solutions.

Q2: What is considered neutral pH?
A: A pH of 7 is considered neutral at 25°C, where [H+] equals [OH-] at 1×10⁻⁷ mol/L each.

Q3: How does temperature affect pH?
A: The pH of neutral water changes with temperature. At higher temperatures, the pH of pure water decreases below 7, but it remains neutral as [H+] = [OH-].

Q4: What are typical pH values for common substances?
A: Battery acid: pH ~0, lemon juice: pH ~2, pure water: pH 7, seawater: pH ~8, bleach: pH ~13.

Q5: Why use logarithmic scale for pH?
A: The logarithmic scale compresses the wide range of hydrogen ion concentrations (from 1 to 10⁻¹⁴ mol/L) into a more manageable scale of 0-14.