What is the pH level of pure water at 25 degrees Celsius?

What is the pH level of pure water at 25 degrees Celsius?

• A. 7.0
• B. 5.0
• C. 9.0
• D. 3.0

Answer: (A)

Pure water at 25 degrees Celsius has a pH level of 7.0, which is considered neutral on the pH scale. The pH scale ranges from 0 to 14, where values below 7 indicate acidity and values above 7 indicate alkalinity. In a neutral solution like pure water, the concentrations of hydrogen ions (H⁺) and hydroxide ions (OH⁻) are equal, resulting in a pH of 7.0. This pH level reflects a balance where the self-ionization of water occurs, represented by the equation: 2 H₂O ⇌ H₃O⁺ + OH⁻ At 25 degrees Celsius, the water has a very specific equilibrium, making the pH level a reliable measure of its neutrality. Factors such as temperature, impurities, or the presence of dissolved substances would affect the pH, but under standard conditions, pure water consistently maintains this neutral pH of 7.0.

Pure water at 25 degrees Celsius has a pH level of 7.0, which is considered neutral on the pH scale. The pH scale ranges from 0 to 14, where values below 7 indicate acidity and values above 7 indicate alkalinity. In a neutral solution like pure water, the concentrations of hydrogen ions (H⁺) and hydroxide ions (OH⁻) are equal, resulting in a pH of 7.0.

This pH level reflects a balance where the self-ionization of water occurs, represented by the equation:

2 H₂O ⇌ H₃O⁺ + OH⁻

At 25 degrees Celsius, the water has a very specific equilibrium, making the pH level a reliable measure of its neutrality. Factors such as temperature, impurities, or the presence of dissolved substances would affect the pH, but under standard conditions, pure water consistently maintains this neutral pH of 7.0.