SELENIDE
A selenide contain the anion Se(2-).
The Se2- ion has the largest radius because it has more electrons than As3-, leading to increased electron-electron repulsion and a larger atomic radius.
O, O2-, S2-, and Se2-O is smaller than O2- because O2- has 2 extra electrons but the same amount of protons as O, so they are held less tightly and the atom is bigger. Atom size increases as you move down the periodic table, so O2- < S2- < Se2-.
The oxidation states of selenium are: -2, +2, +4, +6.
Hydrogen Selenide and it is extremely toxic when inhaled.
A selenide contain the anion Se(2-).
Se2-
When selenium gains two electrons, it becomes the selenide ion.
The Se2- ion has the largest radius because it has more electrons than As3-, leading to increased electron-electron repulsion and a larger atomic radius.
Formula: Se2-
O, O2-, S2-, and Se2-O is smaller than O2- because O2- has 2 extra electrons but the same amount of protons as O, so they are held less tightly and the atom is bigger. Atom size increases as you move down the periodic table, so O2- < S2- < Se2-.
The oxidation states of selenium are: -2, +2, +4, +6.
Hydrogen Selenide and it is extremely toxic when inhaled.
isoelectronic
None. The Se2- ion is isoelectronic with Krypton.
Krypton (Kr) has the same Lewis structure as Se2. Both molecules have 16 valence electrons arranged in a linear structure with a single covalent bond.
Selenium typically forms an ion with a charge of -2 when it gains two electrons to achieve a stable electron configuration. This forms the selenide ion (Se2-).