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How does electron transfer form sodium chloride from sodium and chlorine?

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Two diagrams show the three-dimensional structure of a methane molecule: panel A uses a ball-and-stick model with a central carbon atom connected to four hydrogen atoms in a tetrahedral arrangement, while panel B illustrates the bond angle of 109.5 degrees and bond length of 1.09 angstroms between carbon and hydrogen atoms. — chemical compound Methane, in which four hydrogen atoms are bound to a single carbon atom, is an example of a basic chemical compound. The structures of chemical compounds are influenced by complex factors, such as bond angles and bond length.

The formation of sodium chloride occurs through the transfer of a valence electron from a sodium atom to a chlorine atom, resulting in the creation of an ionic bond.12

The Process of Electron Transfer

Atoms tend to gain or lose electrons to achieve a stable configuration in their outer orbitals.2
* Sodium (Na): As an alkali metal, sodium has one valence electron in its outermost orbital. It readily loses this electron to become a positively charged cation, Na $^{+}$ , thereby exposing its stable inner core.12
* Chlorine (Cl): Chlorine has an incomplete outer shell and readily accepts the electron released by the sodium atom. By gaining this electron, it forms a negatively charged anion, Cl $^{-}$ , completing its valence shell.12

Stability and Lattice Energy

While the initial ionization of sodium requires an input of energy, the overall process is energetically favorable due to the strong electrostatic attraction between the resulting Na $^{+}$ and Cl $^{-}$ ions. As these ions pack together into a crystalline array, they release a significant amount of energy known as lattice energy, which stabilizes the solid compound.13