At what temperature does pure water freeze on the Celsius scale?

• A. 0
• B. 32
• C. 100
• D. -273

Answer: (A)

Verified step by step guidance

1. Understand that the freezing point of pure water on the Celsius scale is a fundamental physical property defined as the temperature at which water changes from liquid to solid under standard atmospheric pressure.
2. Recall the Celsius temperature scale, which is based on two fixed points: the freezing point of water and the boiling point of water at 1 atm pressure.
3. Identify that the freezing point of pure water is set at 0 degrees Celsius by definition.
4. Recognize that 32 degrees corresponds to the freezing point of water on the Fahrenheit scale, not Celsius.
5. Note that 100 degrees Celsius is the boiling point of water, and -273 degrees Celsius corresponds to absolute zero, the lowest possible temperature, not related to water's freezing point.