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pH Formula:
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pH is a measure of the acidity or basicity of an aqueous solution. It is defined as the negative logarithm (base 10) of the hydrogen ion concentration. The pH scale typically ranges from 0 to 14, with 7 being neutral, values below 7 acidic, and values above 7 basic.
The calculator uses the pH formula:
Where:
Explanation: The pH scale is logarithmic, meaning each whole pH value below 7 is ten times more acidic than the next higher value, and each whole pH value above 7 is ten times more basic than the next lower value.
Details: pH measurement is crucial in various fields including chemistry, biology, medicine, environmental science, and agriculture. It affects chemical reactions, biological processes, water quality, and many industrial processes.
Tips: Enter hydrogen ion concentration in mol/L. The value must be positive and greater than zero. The calculator will compute the corresponding pH value.
Q1: What is the normal pH range for drinking water?
A: The EPA recommends that drinking water should have a pH between 6.5 and 8.5.
Q2: How does temperature affect pH?
A: The pH of pure water decreases with increasing temperature due to changes in water's autoionization constant, though the solution remains neutral.
Q3: What is the relationship between pH and pOH?
A: pH + pOH = 14 at 25°C, where pOH = -log[OH⁻]. This relationship comes from the ion product of water.
Q4: 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 most applications.
Q5: How accurate is the pH calculation?
A: The calculation is mathematically precise, but actual pH measurements may vary due to temperature effects, ionic strength, and other factors that affect hydrogen ion activity.