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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 hydronium ion concentration [H₃O⁺]. The pH scale typically ranges from 0 to 14, with 7 being neutral.
The calculator uses the pH formula:
Where:
Explanation: The formula calculates pH by taking the negative logarithm of the hydronium ion concentration in moles per liter.
Details: pH measurement is crucial in chemistry, biology, medicine, environmental science, and many industrial processes. It helps determine the acidity or alkalinity of solutions, which affects chemical reactions, biological functions, and environmental conditions.
Tips: Enter the hydronium ion concentration in mol/L. The value must be greater than 0. The calculator will compute the corresponding pH value.
Q1: What is the range of pH values?
A: pH values typically range from 0 (very acidic) to 14 (very basic), with 7 being neutral. However, values outside this range are possible for extremely concentrated solutions.
Q2: How is pH related to pOH?
A: pH and pOH are related by the equation: pH + pOH = 14 at 25°C. This relationship comes from the ion product of water (K_w = [H⁺][OH⁻] = 10⁻¹⁴).
Q3: Why is pH important in biological systems?
A: Most biological processes are pH-sensitive. Enzymes, proteins, and cellular functions often work within specific pH ranges. Human blood, for example, maintains a pH around 7.4.
Q4: How does temperature affect pH?
A: Temperature affects the dissociation of water, changing the neutral point. Pure water has a pH of 7.0 at 25°C, but this changes with temperature.
Q5: Can pH be negative or greater than 14?
A: Yes, for extremely concentrated acids, pH can be negative, and for extremely concentrated bases, pH can exceed 14. These are not common in most applications.