Meaning of KRYPTON in English
Atomic number: 36
Atomic weight: 83.80 (1) g m
Group in periodic table: 18
Group name: Noble gas
Period in periodic table: 4
Block in periodic table: p-block
CAS registry ID: 7439-90-9
Krypton is present in the air at about 1 ppm. The atmosphere of Mars contains a little (about 0.3 ppm) of krypton. It is characterised by its brilliant green and orange spectral lines. The spectral lines of krypton are easily produced and some are very sharp. In 1960 it was internationally agreed that the fundamental unit of length, the metre, should be defined as 1 m = 1,650,763.73 wavelengths (in vacuo) of the orange-red line of Kr-33.
Under normal conditions krypton is colourless, odourless, fairly expensive gas. Solid krypton is a white crystalline substance with a face-centered cubic structure which is common to all the "rare gases". Krypton difluoride, KrF2, has been prepared in gram quantities and can be made by several methods.
Chemistry of the elements English vocabulary. Английский словарь химии элементов. 2012