Gasthermometers en de Kelvin-schaal

A gas thermometer evaluates temperature based on changes in pressure or volume of the gas-filled.

There are two types of gas thermometers: constant-volume, and constant-pressure, and the constant-volume gas thermometer is the most widely used.

The principle of this thermometer is that, at constant volume, the pressure of a gas increases as temperature increases.

To calibrate the gas thermometer, the pressure at 0 and 100 degrees Celsius is measured.

These values are plotted in a straight line, which is extrapolated to find the zero-pressure temperature.

This temperature is the zero point of the Kelvin scale. This is the standard scale for temperature, as the SI unit of temperature is Kelvin.

Absolute zero is the lowest possible temperature that ideally reflects the utter absence of thermal energy.

On the Kelvin scale, the freezing point of water is 273.15, while the boiling point is 373.15. The difference is the same as on the Celsius scale; only the zero point is different.

Thus, the relationship between Kelvin and Celsius scales can easily be established.