The unit of temperature for all gas problems is Kelvin. Whereas the celsius scale is based on the boiling point and freezing point of water, 0 ºC and 100 ºC respectively, the Kelvin scale is based on the lowest possible temperature absolute zero, which is 0 K. There are no negative numbers in the Kelvin scale.

To convert between celsius and Kelvin temperatures, use the following equation:

The boiling point of water is 100 ºC. In Kelvin, the boiling point of water is:

The freezing point of water is 0 ºC. In Kelvin, the freezing point of water is:

Absolute zero is 0 K. In celsius, absolute zero is: