Re: Why name 'helium' ?

The first thing to make clear is that the explanation is a matter of 
history, and not a matter of chemistry. There is nothing about the 
chemistry of helium that means it should be named in a different way to the 
other noble gases.

The second thing is that helium is not the only non-metal ending in '-ium'. 
We also have selenium. And tellurium and germanium are 'semi-metals' in the 
border-land between metals and non-metals. And although there are several 
'-on' non-metals other than the noble gases -- boron, carbon, silicon -- we 
should never forget iron! ;-)

The third thing is that names of elements vary with language -- much less 
than they might, but significantly. And even in English we have the well 
known battles between sulphur and sulfur, and between aluminium and 
aluminum. The first name is, in each case, the British/European preferred 
form, and the latter name the North American preferred form; the 
International Union of Pure and Applied Chemistry compromised with sulfur 
(American) and aluminium (British).

All five of the stable noble gases were discovered by Ramsay and co-workers 
in the space of about five years from 1894 (Argon) to 1898 (Xenon). It is 
the only instance of a whole group of elements being discovered by one 
research team. But helium was something of a special case. Ramsay chose the 
names for argon, neon, krypton, and xenon, from the Greek words for lazy, 
new, hidden, and stranger. But the existence of helium was already 
suspected several decades before Ramsay isolated it, because of a 
characteristic set of lines in the spectrum of the sun. In 1869, Lockyer 
and Frankland suggested the name 'helium' for an unknown element that 
produced these lines. They had not the slightest idea whether this missing 
element was a metal or a non-metal. Ramsay decided to retain this name.

It was highly appropriate to name this element after the sun, where its 
presence was detected long before it could be on earth, and where it forms 
a few percent of the material as against being a very rare element on 
earth. Missing out on the '-on' ending was a pity, but 'helon' does not 
porperly produce the 'helios' for sun, while 'helion' sounds more like some 
sort of particle, an ion of some sort, rather than the name of a chemical 
element. So all in all helium was a good choice. The names of the elements 
are not systematic.