pH to pOH Converter

What is pH?

pH is a scale used to measure how acidic or basic (alkaline) a water-based solution is. The scale typically ranges from 0 to 14:

• pH less than 7: The solution is acidic. The lower the pH, the stronger the acid. (e.g., lemon juice, stomach acid)
• pH equal to 7: The solution is neutral. (e.g., pure water)
• pH greater than 7: The solution is basic (or alkaline). The higher the pH, the stronger the base. (e.g., baking soda, soap)

pH is based on the concentration of hydrogen ions ([H⁺]) in a solution. It's a logarithmic scale, meaning a change of 1 pH unit represents a tenfold change in acidity or basicity.

What is pOH?

Just like pH measures hydrogen ion concentration, pOH measures the concentration of hydroxide ions ([OH⁻]) in a solution. While pH is more commonly used, pOH is equally important for understanding acid-base chemistry, especially for basic solutions.

At 25°C, there's a simple and crucial relationship between pH and pOH in any aqueous solution:

• pH + pOH = 14

This relationship comes from the self-ionization of water, where a small amount of water molecules break apart into H⁺ and OH⁻ ions. The product of their concentrations is a constant, known as the water dissociation constant (Kw).

Why are pH and pOH Important?

Understanding and measuring pH and pOH is vital in many fields:

• Biology and Medicine: The pH of blood and other bodily fluids must be kept within a very narrow range for health.
• Environmental Science: Monitoring the pH of lakes, rivers, and soil is crucial for ecosystem health and agriculture.
• Food and Beverage Industry: pH affects taste, preservation, and safety of food products.
• Water Treatment: pH control is essential for safe drinking water and wastewater management.
• Industrial Processes: Many chemical reactions and manufacturing processes require precise pH control for optimal results.
• Everyday Life: From shampoo to cleaning products, pH plays a role in how things work.

Common pH Values You Might Encounter

Here are some typical pH values for common substances:

• Battery Acid: ~0-1 (Very Acidic)
• Stomach Acid: ~1-3 (Acidic)
• Lemon Juice: ~2 (Acidic)
• Coffee: ~5 (Slightly Acidic)
• Pure Water: 7 (Neutral)
• Blood: ~7.4 (Slightly Basic)
• Baking Soda Solution: ~9 (Basic)
• Soap/Ammonia: ~10-11 (Basic)
• Bleach: ~12-13 (Very Basic)