Leiden scale to be true. Oxygen under a standard atmosphere boils at a temperature in the 90.15 to 90.18 K range. For hydrogen, it depends on the molecular variety. The boiling point is 20.390 K for "normal" hydrogen (made up of 75% orthohydrogen and 25% parahydrogen) and 20.268 K for pure parahydrogen. Under the purported definition, absolute zero would lie at -20.15 °L. Leiden scale The Leiden scale (°L) was used to calibrate low-temperature indirect measurements in the early twentieth century, by providing conventional values (in kelvins, then termed "degrees Kelvin") of helium vapour pressure. It was used below -183°C, the starting
Planck temperature scale Planck temperature scale The Planck temperature scale is an absolute temperature scale using natural units. On this scale, 0 is absolute zero, and 1 is the Planck temperature. Quantum Theory states that the Planck temperature is the hottest possible temperature. The symbol used for this scale is "T". The freezing/melting point of water on this scale would be written 1.928 × 10"T". A way of expressing temperatures in more familiar sized units is to use centimicroyocto plank temperatures (cµy"T"). The freezing point of water is 1.928 × 10"T". By simply moving the decimal point 32 places to the right, you