Red Phosphorus

[YT2095]

I`m awaiting shipment of 100g of red phos, I was wondering if there`s a solvent for it?

White phos will dissolve in some oils quite easily, I`ve just tried RP in Methyl benzene (as it works great with Sulpher), it doesn`t appear to have done anything at all, even upon heating to boiling point.

polar and non polar solvents at face value don`t seem to have a great effect upon RP.

and I don`t want something that`s going to react with it, just dissolve it.

any thoughts?

[encipher]

I beleive red phosphorus is insoluble in anything, but it's pretty stable (other than the toxic fumes of course =D ). I guess I'd store it under water like white phosphorus.

[YT2095]

Trust Me to choose the one experiment that wouldn`t give a result!

I thought I could tempt it into forming a Sesquisulphide, so I dissolved a little sulpher in the toluene and reheated it, still did nothing.

 

as for storing RP under water, it`s an unecessary precaution, the addition of a little Calcium Carbonate and it`ll store indefinately anyway

[jdurg]

My Red Phosphorus powder is stored in a standard glass vial with the cap tightly affixed. It's been that way for a few years now and it's still perfectly ok.

 

On a side note, earlier today I was looking through Alpha Aesar's online catalog of pure elements and REALLY wished that I had a business I could be associated with and a corporate credit card. Some of the elements they have there are actually pretty decently priced. I saw the Red P for sale at INCREDIBLY dirt cheap prices.

[YT2095]

Hmmm.. I have a card AND a business, yer making me wish I`de gone there 1`st now!

 

anyway, so there`s no known solvent for RP then?

[woelen]

Red P does not dissolve in any solvent. Red P forms macroscopic molecules, like graphite, diamond, boron and silicon. These compounds cannot be dissolved without chemical reaction. This can also easily be explained. Dissolving of these compounds means that bonds are broken. This is in large contrast with sulphur, white P and red selenium. These form molecules (S8, P4, Se8), which can be separated more easily, without the need to break chemical bonds. So, for these, there are quite some solvents.

 

Red P can also be stored indefinitely, if stored in a tightly capped container. It is not poisonous and it is quite stable. Only at elevated temperatures and in contact with elemental halogens (especially Cl2 and Br2, but to a lesser extent, also I2) it is reactive. Otherwise it is remarkably inert.

[person]

Sorry to bring this up. I know its old but...

 

Why is white P so reactive ? It has a higher electonegativity than H2 and you dont see H2 spontanously combusting in air ? It clearly has something to do with alotropes wich brings me to my next question...

 

And also by what mechanism do alatropes affect reactivity ?

 

Is there a (relatively) simple way to calculate the reactivity (eg equivilent electronegativity) of a alatrope ?

 

Thanx

[Sebbass69]

Sorry to bring this up. I know its old but...

 

Why is white P so reactive ? It has a higher electonegativity than H2 and you dont see H2 spontanously combusting in air ? It clearly has something to do with alotropes wich brings me to my next question...

 

And also by what mechanism do alatropes affect reactivity ?

 

Is there a (relatively) simple way to calculate the reactivity (eg equivilent electronegativity) of a alatrope ?

 

Thanx

 

From what I understand, the tetrahedral arrangement of the phosphorus atoms puts extremely high strain on the bonds - this makes them more reactive.

[person]

Why does it form these bonds in the first place then ?

 

Thanx

[Theophrastus]

Molecular geometry, really has much to do with the number of valence electrons, and the type of bonds present and the like (double, single, sigma pi). Generally, I'd elaborate, though I'm feeling lazy. Simply google molecular geometry, and I'm sure you'll find the answer, typing in several of the keywords above.