Krypton is a noble gas, which means it is very unreactive. Its chemical symbol is Kr, and it has the atomic number 36.

Krypton is colorless, odorless, and tasteless in its natural state.

It is heavier than air, which allows it to be collected through fractional distillation of liquid air.

Krypton occurs in trace amounts in the Earth’s atmosphere at about 1 part per million.

The name Krypton comes from the Greek word kryptos, meaning “hidden.”

It was discovered in 1898 by Sir William Ramsay and Morris Travers.

Krypton belongs to Group 18 on the periodic table.

It has a melting point of minus 157.37 degrees Celsius and a boiling point of minus 153.22 degrees Celsius.

Krypton is monatomic, meaning it exists as single atoms rather than molecules.

Its density is 3.749 grams per liter at 0 degrees Celsius, making it denser than oxygen or nitrogen.

Krypton emits a vivid greenish yellow glow when electrified in a gas discharge tube.

It has several isotopes, with Kr 84 being the most abundant at about 57 percent.

Krypton is slightly soluble in water.

Under high pressure, it forms crystalline solids.

Its atomic radius is approximately 88 picometers.

Krypton is nonflammable.

The gas is chemically inert and forms only a few compounds under extreme conditions.

It remains monatomic even at extremely low temperatures, unlike oxygen or nitrogen.

Krypton is used in high performance lighting, including fluorescent lamps and high intensity discharge lamps.

It is used in certain photographic flashes, including early strobe technology.

Krypton gas can serve as an insulating material in energy efficient windows.

Krypton is used in some lasers, especially krypton ion lasers that produce visible light across multiple colors.

It is used in plasma physics and experimental fusion research.

Krypton 85, a radioactive isotope, is used in thickness gauges and for detecting leaks in sealed systems.

Krypton is occasionally used in space exploration experiments.

It is also used in some forms of medical imaging.

Krypton lasers are used in eye surgery and dermatology.

Krypton is used in research involving extremely low temperature physics.

Krypton has more than thirty known isotopes, most of which are unstable.

Krypton 81 is used to date ancient groundwater.

Krypton 85 is produced as a byproduct of nuclear fission.

Some isotopes of krypton are radioactive with half lives ranging from seconds to millions of years.

Krypton 86 was once used to define the length of the meter in 1960 through its spectral emission lines.

Krypton isotopes help trace patterns in atmospheric circulation.

Radioactive krypton can serve as a tracer for monitoring nuclear activity.

Stable krypton isotopes include Kr 78, Kr 80, Kr 82, Kr 83, and Kr 84.

The isotope Kr 82 is sometimes used in specialized laser applications.

Krypton isotopes are produced naturally in very small amounts within the atmosphere.

Krypton was discovered shortly after neon, another noble gas identified by William Ramsay, who also discovered argon, neon, and xenon.

The name referencing something “hidden” reflects how difficult krypton was to detect in the atmosphere.

Krypton is rarer than neon but more common than xenon.

It can form krypton difluoride, also written as KrF2, under extreme conditions, which is one of the few known krypton compounds.

Krypton compounds are highly reactive, unlike the stable gas itself.

Krypton is used in scientific demonstrations because of its bright green or orange spectral lines.

Krypton is non toxic but can cause suffocation if it displaces oxygen in high concentrations.

Krypton is a niche element, often recognized more for its connection to Superman than for practical everyday applications.