how do halogens appear in nature?

quicksilver123

i've been given an assignment in which i'm supposed to find some characteristics of different halogens.

they're all listed as atoms paired with themselves.
eg.
F₂
I₂
ect

are halogens normally expressed this way?

Specifically, I was asked to investigate Astintine. However, I wasn't told whether its the astintine molecule or atom.
Assuming its the molecule, would it be:
At₂ ?

Borek

So, what is the question, because you asked for something else in the subject, and then for something else in the body?

quicksilver123

It won't let me edit it.

Do halogens appear this way in nature?
(also, the body question)

SteamKing

You should know that element 85 is astatine, not astintine.

I don't know what 'ect' stands for, but 'et cetera' is abbreviated 'etc.'

trollcast

Halogens only occur as compounds in nature due to their high reactivity.

However if you are talking about the chemical properties of pure astatine you could get a general idea of what they must be by looking at the trends observed in the other elements as you move down the group from Fluorine to Iodine.

http://en.wikipedia.org/wiki/Halogen...cal_and_atomic
That will give you a simple table showing the chemical properties of the other halogens.

http://www.chemguide.co.uk/inorganic...roperties.html
Or that goes into a bit more detail and explains why some of the trends occur.

quicksilver123

unhelpful troll is unhelpful

i'm a chem noob. thanks for the links

snorkack

Oddly, even the most active element, fluorine, occurs free in the natural mineral stinkspar!
Yes, but the properties of free astatine are somewhat difficult to ascertain due to the difficulties in producing and keeping bulk quantities.

Looking at the other main groups:
In Group 4, all elements from C to Sn inclusive form covalent bond networks with 4 covalently bound nearest neighbours - but Sn also has metallic forms with 6 nearest neighbours, and Pb always is face-centered cubic with 12 nearest neighbours.
In Group 5, yellow phosphorus consists of P4 molecules but these get crosslinked on prolonged heating; yellow arsenic gets crosslinked rapidly; Sb4 molecules may not even exist in condensed form; Bi has only one allotrope which is clearly metallic
In Group 6, S8 molecules are, on low temperature, more stable than long chains. Se8 molecules can be isolated, but on heating they convert to the stable long spiral packing; Te only occurs in the (covalent, semiconductive) packing of chains; but Po has 2 allotropes which are both clearly metal.

So... would At condense into weak crystals of At2 molecules? Or would they find ways to crosslink into some kinds of covalent nonmetal, semimetal or metal networks?