The first noble gas to be discovered was

Options

A. argon
B. helium
C. xenon
D. radon

Answer

2

Explanation

Although it had been noted as early as `1785` that there was something else in air besides `O_(2)` and `N_(2)` it was not until `100` years later that Sir william Ramsay showed that this other gas produced a previously unknown spectrum when an electric discharge was passed through it .Because every element has a unique spectrum, the gas producing the new spectrum had to be a new element .He named it argon, from the Greek word for lazy, because of its inertness (unreactive nature), and he suggested that if might be the first member of a new group in the periodic table.
In fact one other element in this group 'helium' has already been discovered in `1868` but not on Earth's Observation of the spectrum of the sun had shown some lines that did not belong to any element known at that time.The new element was named hel-ium ,the first pat of the name indicating that it was first discovered inthe sun (greek ,helions) and the ending indicating that it was exceptd to be a metal.
The element `He` was first isolated on Earth in `1894` from produced during the radioactive decay of `U` and its daughter elements. In `1926` it was suggested that the name of the element be changed to helion, to indicate that it was not a metal, but by that time the former name was too well established.