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pH Formula:
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The pH formula is a fundamental equation in chemistry that calculates the acidity or basicity of a solution. It is defined as the negative logarithm (base 10) of the hydrogen ion concentration [H⁺].
The calculator uses the pH formula:
Where:
Explanation: The formula calculates the negative base-10 logarithm of the hydrogen ion concentration, providing a scale from 0 to 14 where values below 7 are acidic, 7 is neutral, and above 7 are basic.
Details: pH measurement is crucial in various fields including chemistry, biology, environmental science, medicine, and industry. It helps determine the acidity or alkalinity of solutions, which affects chemical reactions, biological processes, and material properties.
Tips: Enter the hydrogen ion concentration in moles per liter (mol/L). The value must be greater than 0. For very small concentrations, scientific notation may be helpful (e.g., 1e-7 for 0.0000001 mol/L).
Q1: What is the range of pH values?
A: pH values typically range from 0 to 14, with 7 being neutral. Values below 7 are acidic and values above 7 are basic (alkaline).
Q2: How is pH related to pOH?
A: pH and pOH are related by the equation: pH + pOH = 14 at 25°C. pOH is calculated as -log[OH⁻], where [OH⁻] is the hydroxide ion concentration.
Q3: 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.
Q4: What are some common pH values?
A: Pure water has pH 7, lemon juice ~2.4, vinegar ~3, coffee ~5, blood ~7.4, seawater ~8, ammonia ~11.
Q5: How does temperature affect pH?
A: The pH of neutral water decreases with increasing temperature due to changes in the water dissociation constant, though the solution remains neutral.