For individual atoms, the Lewis structure is drawn by placing a dot around the atom for each valence electron available. Octet rule states that in forming compounds, atoms gain, lose or share electrons to give a stable electron configuration characterized by eight valence electrons.

Description. Radium selenide has the molecular formula of RaSe and the molecular weight of 304.984985 g/mol. It has the CAS number of 23320-14-1. It reacts with water so that an aqueous method of precipitation cannot be used to prepare this compound.

Aluminum selenide

Al2Se3

For example, when two chlorine atoms, each with 7 valence electrons, come together to form a diatomic chlorine molecule, the Lewis structure shows that there will be a sharing of two electrons between the two chlorine atoms which allows both chlorine to be surrounded by 8 electrons….Lewis Dot Structures.

Every carbon, nitrogen, oxygen, and fluorine atom in this molecule has a full octet. All atoms in this molecule have a complete valence electron count.

✔️In chemistry, the octet rule explains how atoms of different elements combine to form molecules. In a chemical formula, the octet rule strongly governs the number of atoms for each element in a molecule. ✔️For example, calcium fluoride is CaF2 because two fluorine atoms and one calcium satisfy the rule.

The octet rule refers to an important principle that the atoms which have bonded share eight outer electrons. This certainly means that the atom’s valence shell has a resemblance with a noble gas. The octet rule states that the atoms like to have eight electrons only in their full outer shells.

The octet rule states that atoms tend to form compounds in ways that give them eight valence electrons and thus the electron configuration of a noble gas. An exception to an octet of electrons is in the case of the first noble gas, helium, which only has two valence electrons.

This is known as the octet rule. The stable octet can be achieved by the transfer of electrons or by sharing of a pair of electrons between the atoms. In this process, each atom attains a stable outer octet of electrons.

Limitations of the octet theory: (d) The octet rule is not satisfied for all atoms in a molecule having an odd number of electrons. For example, NO and NO2 do not satisfy the octet rule. (e) This rule cannot be applied to those compounds in which the number of electrons surrounding the central atom is less than eight.

Limitations of the octet theory: 1) The main limitation to the rule is hydrogen, which is at its lowest energy when it has two electrons in its valence shell. Helium (He) is similar in that it, too, only has room for two electrons in its only valence shell. Hydrogen and helium have only one electron shell.

Chlorine has seven valence electrons, so if it takes one it will have eight (an octet). Chlorine has the electron configuration of argon when it gains an electron.