What unit of measurement is used to express the freezing point of water in the Kelvin scale?

The freezing point of water, when expressed in the Kelvin scale, is 273.15 K. This relationship stems from the absolute temperature scale, which is based on the concept of absolute zero, the point at which molecular motion stops. In the Celsius scale, water freezes at 0 degrees Celsius. To convert this to Kelvin, you add 273.15, resulting in 273.15 K.

The Kelvin scale is commonly used in scientific contexts because it provides a direct way to compare thermal energy and states of matter without negative numbers. Therefore, when asked for the freezing point of water in Kelvin, 273.15 K is the correct value because it accurately reflects the transition of water from the liquid state to the solid state at that temperature.