[siriusmd99]

I have one problem to solve:
 I have water and air. With available technical means and without using of other chemical substances, catalysts except , how i can obtain salt?
I should write also reaction's equations.

[Arkcon]

I suspect we may be facing a language issue, but your question makes very little sense.  If you read it carefully, surely you see that you're trying to create something from nothing, and anyone should realize that's impossible.  If I've over-simplified, you will have to try to describe your question more completely and carefully.

[siriusmd99]

 I have to obtain salt from water and air without other substances.

[Spazcat]

I have to obtain salt from water and air without other substances.

If you mean Saltwater, you could either evaporate it or distill it.
But if you mean fresh water, it's not possible, there's no salt in fresh water, or there shouldn't be...

[siriusmd99]

You don't understand i mean that i have to obtain salt from AIR and WATER .

Not from SaltWater but from AIR AND WATER.

[Spazcat]

You don't understand i mean that i have to obtain salt from AIR and WATER .

Not from SaltWater but from AIR AND WATER.

From my understanding, there's no possible way of this.
You have O₂, N₂ And some other gasses + H₂O.

Do you understand there is no way of doing this as there is no Na or Cl in either substance.

Perhaps I am misinterpreting this whole thing, but if this is a textbook or homework question, could you write it out exactly as is, or maybe take a picture?

[siriusmd99]

Yes it's my homework .
It writes that you can use only catalyst.

[Spazcat]

I'm sorry, I see no way of doing this, even with a catalyst.
Catalysts aren't consumed in a reaction so they can't offer us the Sodium or Chlorine we need.

[Borek]

Hint: Haber-Bosh process.