Argon

On the periodic table, argon is in period 3 and group 18. Argon's atomic mass is about 40 kg and its atomic number is 18. Argon is one of the six noble gases, it is classified as that because it is non-reactive to any other elements

Argon was discovered by Lord Rayleigh, an English chemist, and William Ramsay, a Scottish chemist, in 1894. They were conducting an experiment where they took a sample of clean air and removed all oxygen, carbon dioxide, water, and nitrogen, leaving them with one final element of Argon.

Argon is mostly found as a element, especially in the atmosphere since it makes up about 1% of the atmosphere, making it the Earth's third most abundant gas. Argon does have a compound called Argon Fluorohydride ( HArF), but it was not discovered until  the 2000's.

To get argon in its pure form, you would have to boil liquid air (pressurized) until the liquid nitrogen would boil out at 77.3 degrees kelvin.

Today argon is used for, thermal insulation in windows, incandescent lighting, inflating dry suits in scuba diving, and in fluorescent light bulbs.