the aspect of helium in the periodic table

I have been trying to get an answer to the helium question. The question is that why helium is placed in group 18 in the periodic table but not placed in group 2 or in alkali-earth metal groups.
thanks for the help

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It has a full shell; unreactive.
IT should therefore be with all the other halogens, which all have full shells of 8, 18 or 32.

Contraversially, H should really be placed over Carbon - it does not act like any of the group I elements (yes, it has just 1 electron, but it doesn't lose it in all reactions). H shares it's electron a lot more, and it has a half full shell.... just like Carbon!

[quote="allan_chemist"]It has a full shell; unreactive.
IT should therefore be with all the other halogens, which all have full shells of 8, 18 or 32.
[/quote]

I assume you meant noble gas :)

Re: the aspect of helium in the periodic table

[quote="lionkings"]I have been trying to get an answer to the helium question. The question is that why helium is placed in group 18 in the periodic table but not placed in group 2 or in alkali-earth metal groups.
thanks for the help[/quote]

The answer for the first part of the question is easy, as allan_chemist's answer. However, I'm just thinking that why the question ask 'why not in group 2'. If this should be answered as well? The question seems a bit strange.

yes. I still couldnt get the answer for the reasons not placing Helium in group 2 or in alkali-earth metal groups. your help is appreciated.

yes, it's true

The simple answer is:
the whole point of the periodic table is to lay out the elements in a way which best summarizes their chemical behaviour.

Helium behaves very similarly to the rest of the noble gases.
It has no chemical similarities whatsoever with the alkaline earth metals.

Therefore, put it in group 18! The end. :D

(Bear in mind that orbitals and electron shells are all just made up. They don't really exist. But chemical properties do. They are real. And much more important. So they take priority when deciding where to put things)

[quote="UCB Mitch"][quote="allan_chemist"]It has a full shell; unreactive.
IT should therefore be with all the other halogens, which all have full shells of 8, 18 or 32.
[/quote]

I assume you meant noble gas :)[/quote]
Yes
¬_¬

I was thinking "What's the trivial name again..."
Then I thoguth of a halogen light, and assumed that you won't use chlorine in one of them, so it must be the noble gasses..
WRONG
:?

I am a chemist.....honest...

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