Symbol

Kr

Atomic Number

36

Atomic Mass

83.80

Family

Group 18 (Viiia) Noble Gas Pronunciation

KRIP-ton

Overview

Krypton was one of three noble gases discovered in 1898 by Scottish chemist and physicist Sir William Ramsay (1852-1916) and English chemist Morris William Travers (1872-1961). Ramsay and Travers discovered the gases by allowing liquid air to evaporate. As it did so, each of the gases that make up normal air boiled off, one at a time. Three of those gases—krypton, xenon, and neon, were discovered for the first time this way.

The term noble gas refers to elements in Group 18 (VIIIA) of the periodic table. The periodic table is a chart that shows how chemical elements are related to each other. These gases have been given the name "noble" because they act as if they are "too arrogant" to react with other elements. Until the 1960s, no compound of these gases was known...