I didn't realise it was in solid state. I just assumed water would be the solvent.
But then, are you using HCl as a gas?!?
In this case, you may have some ion exchange. For example, some Na
+ from NaNO
3 will move with the Cl
- from HCl (I keep wondering how you can get HCl gas within the solid before it flies away... have you tried? It is a toxic gas) to form NaCl.
During the grinding, you can possibly have a bit of decomposition of NO
3- into NO
2 gas + O
2- which will then form some oxides.
So, at the end after thoroughly grinding your solid, you should be left with a mixture of NaNO
3, NaI, NaCl, Na
2O and some gases released into the atmosphere.
An element has oxidation 0 when it has the same number of electrons and protons. If the element gains 1 electron, the oxidation number decrease by 1. If it loses one electron, the oxidation number increases by 1.
For ZnCl
2, you have Zn
2+ (oxidation +2) and Cl
- (oxidation -1). Cl is more electronegative than Zn, so it takes one electron for itself.
For H
2, the 2 electrons from the covalent bond are equally share between the two atoms
each hydrogen has one electron and one proton in its nucleus
oxidation 0.
As a general rule, in case of molecules made of only one element and electrically neutral, the element has an oxidation number of 0. Example: H
2, N
2, O
2, S
8,...
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Topic: Chemical equation? (Read 9868 times)