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pH Formula:
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pH is a measure of the acidity or basicity of a solution. It is defined as the negative logarithm (base 10) of the hydrogen ion concentration. The pH scale ranges from 0 to 14, with values below 7 indicating acidity, values above 7 indicating basicity, and 7 being neutral.
The calculator uses the pH formula:
Where:
Explanation: The formula calculates pH by taking the negative logarithm of the hydrogen ion concentration. This logarithmic scale allows for a wide range of concentrations to be represented on a convenient 0-14 scale.
Details: pH measurement is crucial in many fields including chemistry, biology, medicine, environmental science, and agriculture. It affects chemical reactions, biological processes, and the health of aquatic ecosystems.
Tips: Enter hydrogen ion concentration in 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).
Q1: What is the relationship between pH and pOH?
A: pH + pOH = 14 at 25°C. pOH is calculated as -log[OH⁻], where [OH⁻] is the hydroxide ion concentration.
Q2: What is a normal pH range for blood?
A: Human blood typically has a pH between 7.35 and 7.45. Values outside this range can indicate medical conditions.
Q3: How does temperature affect pH?
A: The pH of pure water changes with temperature (pH 7.0 at 25°C, but 6.81 at 100°C), though the neutral point remains when considering the water ion product.
Q4: Can pH be negative or greater than 14?
A: Yes, for very high concentrations of strong acids, pH can be negative, and for very high concentrations of strong bases, pH can exceed 14.
Q5: How accurate is this calculation?
A: This calculation provides the theoretical pH based on hydrogen ion concentration. In practice, actual pH measurements may vary due to temperature, ionic strength, and other factors.