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pH Formula:
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pH is a measure of the acidity or basicity of a solution, defined as the negative logarithm of the hydrogen ion concentration. It ranges from 0 (very acidic) to 14 (very basic), with 7 being neutral.
The calculator uses the pH formula:
Where:
Explanation: The formula calculates the negative logarithm of hydrogen ion concentration to determine the pH value of a solution.
Details: pH calculation is essential in chemistry, biology, environmental science, medicine, and many industrial processes. It helps determine the acidity or basicity of solutions for various applications including water treatment, food processing, and pharmaceutical manufacturing.
Tips: Enter hydrogen ion concentration in mol/L (moles per liter). The value must be greater than 0. For very small concentrations, scientific notation may be helpful (e.g., 1.0e-7 for 0.0000001).
Q1: What is the relationship between pH and [H⁺] concentration?
A: pH decreases as hydrogen ion concentration increases. Each unit change in pH represents a tenfold change in hydrogen ion concentration.
Q2: What is considered neutral pH?
A: At 25°C, pure water has a pH of 7, which is considered neutral. Solutions with pH less than 7 are acidic, while those with pH greater than 7 are basic.
Q3: Can pH be negative or greater than 14?
A: Yes, for very concentrated strong acids, pH can be negative, and for very concentrated strong bases, pH can exceed 14, though these are rare in practice.
Q4: How does temperature affect pH?
A: Temperature affects the autoionization of water, changing the neutral point. At different temperatures, neutral pH may not be exactly 7.
Q5: What are common methods to measure pH?
A: Common methods include pH meters with glass electrodes, pH indicator papers, and color-changing indicators like litmus paper or universal indicator solution.