Learning about gas: Krypton – a rare noble gas

Krypton(Kr) is not just Superman’s home planet, but it’s also one of the rarest gases on Earth. The noble gas, composing only 1 part per million of the atmosphere by volume, is both odour and colorless.

An accidental discovery
The gas was discovered in 1898 by Morris Travers and William Ramsay when the two scientists was trying to find a chemical element to fill the gap between Helium and Argon in the Periodic table. By evaporating nearly all of the components from one liter of liquid air the scientists were left with a heavy gas sample. The gas sample was not what they were hoping for but wondering if they might find something interesting they analyzed the light spectrum of the sample and found something unknown. They called it the hidden gas and later named their discovery after the Greek word for “hidden”, kryptos.

Krypton in short
Symbol: Kr
Molar mass: 83.8 g/mol
Density: 2.41 kg/dm3
Covalent radius: 116 pm
Number of electrons: 36
Vapor pressure: ** at triple point 731 mbar
Melting point: 116 K (-157,36 °C)
Boiling point: 119,8 K (-153,22 °C)

Lighting up our world
Because of the rareness of the gas the use is limited, although recent use of krypton in lightbulbs and energy-saving windows has increased. By using krypton in different light sources the bulb will burn brighter and longer, it will also use less energy. The light created when an electric current is sent through a light source containing krypton gives a white bright light and enables people to see more clearly. The gas is also used as a filler between insulated glass panels and has been a key success in energy-saving windows.

Deadly for Superman – but how about us?

Like mentioned in the beginning, krypton is also the name of the planet where Superman comes from. In the comics the planet explodes do to a nuclear chain reaction caused by an unstable radioactive core, because of this a substance called kryptonite is released. Kryptonite is radioactive chunks which seems to be the only thing deadly to Superman, but how does it affect us?

Well, first of all – kryptonite does not exist in real life, and it would actually be really hard to get some sort of reaction from the gas krypton at all. By being a noble gas, krypton does not combine with other and therefore will not burn or cause corrosion. So, the kryptonite might be deadly for Superman but you will be safe!

By:Mathilda Simonsson
Photo: Shutterstock