Questions about charges of anions/cations?

Question

Through my previous questions I have seen that my teacher has made many mistakes about charges. Therefore, I would like to clear up more discrepancies between my teacher and the book.

My teachers says that nitrogen could form cations of +3 and +5 but I thought nitrogen could only form the anion -3?

Also, I thought phosphorus, arsenic, and antimony formed anions of -3 and not cations of +3?

And could helium form cations of 2+? I thought helium was a noble gas?

Lastly, I thought th at cesium formed cations of 1+ and not anions of 1-?

Am I crazy or is my teacher crazy?

Answer 1

Actually, nitrogen can have the oxidation states of: +1, +2, +3, +4, +5, -1, -2, and -3! (However some of these are not common). -3, +3 and +5 are the common ones.

P, As and Sb all can exist in +3, +5 and -3 states

Whether it is + or - oxidation state depends on what it is combined with, for example in PH3 P is -3 in P2O5 P is +5

He is a noble gas, I have never heard of He+2; maybe it could form under some kind of very bizarre conditions, but nothing normally encountered.

cesium forms a +1 ion;

I don't know if he is crazy or not, you don't have to be crazy to be wrong! What school do you go to anyway?

Answer 2

Cs can only form +1 state of oxydation in normal conditions, of course in the gas phase you can always take or push electrons if you use enough energy.
it's electron affinity is 45.5 kJ/mol, it's so low that even hydrogen prefer to take an electron from cesium like in
CsH, that is cesium hydride Cs+ and H-

cations of nitrogen are in reality more stable than the anion, they are called nitrites+3 and nitrates+5

P, As and Sb do the same.

First ionization energy of helium is 2372.3 kJ/mol
helium is the less reactive element of the periodic table, it's so difficult to take away an electron from helium, but it's possible.
As with the other noble gases, helium has metastable energy levels that allow it to remain ionized in an electrical discharge with a voltage below its ionization potential. Helium can form unstable compounds with tungsten, iodine, fluorine, sulfur and phosphorus when it is subjected to an electric glow discharge, through electron bombardment or is otherwise a plasma. HeNe, HgHe10, WHe2 and the molecular ions He2+, He2++, HeH+, and HeD+ have been created this way. This technique has also allowed the production of the neutral molecule He2, which has a large number of band systems, and HgHe, which is apparently only held together by polarization forces.[1] Theoretically, other compounds, like helium fluorohydride (HHeF), may also be possible.

Answer 3

1 covalent 2 cation 3 atleast one metal 4 non polar covalent 5 cl- and ar 6 ionic 7 mg br2 8 co2 molecules 9 sillicon tetrachloride 10 1-

Answer 4

I may be crazy but it seems that he must be confusing valence and cations. I can't remember anything that could form such a charged particle as +5. It has been several years since I got my degree but my memory is that is not reasonable for a single atom.