The formula would be K2Se
Na2Se.
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The compound formed between sodium and selenium is named "sodium selenide" and has the formula Na2Se.
It is called Selenite; as a polyatomic ion, this compound is an exception to standard molecular compound naming rules. NOTE: It has a combined electrostatic charge of 2-
The chemical formula of aluminium phosphide is AlP.
Sulfur hexachloride is an inorganic compound consisting of two different elements. The prefix hexa indicates that there are six chloride atoms. Thus, the formula is SCl6. Note that this compound does not obey the octet rule.
Organic formula is a formula that shows an organic compound and its molecular arrangement.
FeSe
The manganese(IV) selenide has the chemical formula MnSe2.
That would be chromium(IV) selenide with the formula CrSe2
Na2Se
The compound formed between sodium and selenium is named "sodium selenide" and has the formula Na2Se.
the difference is that the formula does not have the same categories as the chemical compound does
Selenium tetrafluoride is SeF4
Cinnabar (HgS) is the common ore of mercury.Mercuric chloride is a chemical compound with the formula HgCl2.Mercury oxide is the simple oxide with the formula HgO.Mercury selenide is a chemical compound of mercury and selenium with the formula (HgSe).Note this list of compound of mercury is not exhaustive.
The chemical formula of iron(III) and selenium is Fe2Se3 - iron(III) selenide.
Selenium dioxide (SeO2) is the most widely used selenium compound in industry. It is used as an oxidising agent in drug and other chemical manufacture, a catalyst in organic syntheses, and an anti-oxidant in lubricating oils.
It is called Selenite; as a polyatomic ion, this compound is an exception to standard molecular compound naming rules. NOTE: It has a combined electrostatic charge of 2-
The chemical formula for element selenium is indicated by se. Native selenium is a rare mineral which does not usually forms good crystals. Hence it is used in the manufacture of specimens