Final answer:
Water freezes at 32 °F and boils at 212 °F on the Fahrenheit scale; it freezes at 0 °C and boils at 100 °C on the Celsius scale, and on the Kelvin scale, these points are respectively at 273.15 K and 373.15 K. The Celsius and Kelvin scales share the same increment size, whereas the Fahrenheit scale is 9/5 of that size.
Step-by-step explanation:
The freezing points and boiling points of water are key reference temperatures for the three main temperature scales: Fahrenheit, Celsius, and Kelvin. In the Fahrenheit scale, water freezes at 32 °F and boils at 212 °F. The Celsius scale, also known as centigrade, has the freezing point of water at 0 °C and the boiling point at 100 °C. Lastly, the Kelvin scale, which is an absolute temperature scale, has the freezing and boiling points of water at 273.15 K and 373.15 K respectively.
It's important to note that while the Celsius and Kelvin scales share the same increment size, each degree on the Fahrenheit scale is 9/5 the size of a degree on the Celsius or Kelvin scale. Additionally, the Kelvin scale is based on the concept of absolute zero, which is the point where all molecular motion ceases, set at 0 K. Unlike Celsius and Fahrenheit, the Kelvin scale does not use degrees but simply kelvins.