In the compound sodium fluoride, NaF, the sodium atom loses one electron and the fluorine atom gains one electron to form ions that are isoelectric with neon.
In many compounds, atoms of main-group elements form ions so that the number of electrons in the outermost energy levels of each ion is 8.
Ions that have the same number of electrons as a noble gas are said to be isocelectric with the noble gas.
Cations have a positive charge and anions have a negative charge.
When the octet rule is satisfied, the outermost S and P orbitals are filled.
The elements of the noble gas group satisfy the octet rule without forming compounds.
Once an atom has full S and P orbitals in its outermost energy level, it has a stable octet and is unreactive. An octet is equal to 8 electrons. This is the octet rule.
Compounds that have the same number of positive and negative charges are said to be electroneutral.
Two sodium ions, Na 1+, are needed to make a carbonate ion, (CO3) 2- electrically neutral. Na2CO3
Lead (II) ion and lead (IV) ion have charges of 2+ and 4+ respectively.
The chemical formula for an ionic compound represents the simplest ratio of ions that result in an electrically neutral compound.
A shorthand representation of the composition of a substance using atomic symbols and numerical subscripts is called a chemical formula.
A formula that shows the types and numbers of ions combined in a single compound is called an ionic formula.
A formula unit of an ionic compound is the simplest ratio of ions that balances the total charge.
Binary compounds are named with the cation first. The electrostatic attraction between ions forms an ionic bond. An ionic compound is not represented by a molecular formula because an ionic compound lacks molecules.
The salts NaCl and CaCl2 are held together by ionic bonds.
In the NaCl crystal, each Na 1+, and C1-, ion has clustered around it 6 of the oppositely charged ions.
In an ionic compound, the orderly arrangement of ions in a crystal is called the crystal lattice.
The ions of an ionic compound are organized into a crystal.
In a crystal of an ionic compound, each cation is surrounded by anions.
In a crystal, the ions of like charges repel each other.
The simplest repeating unit of a crystal is known as a unit cell.
A particular packing arrangement of ions is known as a crystal lattice.