Oxideit's a substance inorganic binary (formed by two different chemical elements) in which one of the elements is oxygen (acronym O), which is the most electronegative element and presents NOX equal to -2.
General formula of an oxide
See too:What is NOX?
1- Types of oxides
Ionic: are oxides that present metal following the oxygen in the composition;
Molecular: are oxides that present ametal following the oxygen in the composition.
In general, if the oxide is ionic or molecular, we can use the following official naming rule:
Prefix + oxide + de + prefix + element name
Example: Cl2O5 → Dichlorine pentoxide
Note: The prefix is related to the amount of oxygen or the element that accompanies oxygen → 2 (di), 3 (tri), 4 (tetra), 5 (penta) etc.
For ionic oxides, we can use two other rules:
If the element has fixed NOX (belonging to the IA, IIA, IIIA families or is it zinc or silver):
Oxide + de + element name
Example: CaO → calcium oxide
If the element does not have fixed NOX:
Oxide + de + element name + roman numeral
Note: The Roman numeral is the NOX of the element.
Example: Cr2O3 → chromium oxide III
Double, mixed or saline: are ionic oxides that have Y3O4 as a general formula. In water, they form two bases and when they react with acids or bases, they form two salts and water;
-
amphoteres: When these oxides react with acid or base, form salt and water. Can be:
→ ionic oxides that have in their composition the metals beryllium (acronym Be), aluminum (acronym Al), chromium (acronym Cr; NOX +3), zinc (acronym Zn), tin (acronym Sn), lead (acronym Pb);
→ molecular oxides that have the elements antimony (acronym Sb) or arsenic (acronym As).
Basics: ionic oxides that have any other metal (except chromium, which only forms a basic oxide if it has NOX +2). In water they form bases and, in the presence of acid, form salt and water;
Neutrals: are the molecular oxides carbon monoxide (CO), nitrogen monoxide (NO) and dinitrogen monoxide (N2O). Do not react with water, base or salt;
Acids: any other molecular oxide and chromium oxide (provided it has NOX +6). In water, they form acids and, in the presence of a base, form salt and water.
By Me. Diogo Lopes Dias
Source: Brazil School - https://brasilescola.uol.com.br/o-que-e/quimica/o-que-e-oxido.htm
