On the ionic compound of sodium and fluorine
Sodium, a metal, is active and easy to lose electrons. Its atom has an electron arrangement outside the nucleus, and the outermost layer has only one electron. In order to achieve a stable structure, it often leaves this electron and becomes a cation with a unit positive charge.

Fluorine, a non-metallic element, is very strong and has a strong power to grab electrons. Its outermost layer has seven electrons, and it is very eager to get one electron to form an eight-electron stable state, so it often gains electrons to form an anion, with a unit negative charge.

When sodium and fluorine meet, the electrons lost by sodium are exactly obtained by fluorine. The two combine with the attractive force of static electricity to form an ionic compound. In this compound, anions and cations are arranged in an orderly manner and are maintained by ionic bonds.

The ionic compound formed by sodium and fluorine has many characteristics. Its melting and boiling point is quite high, and the cover ionic bond is strong. To melt or boil it requires a lot of energy to break this bond. And in the molten state or aqueous solution, it can conduct electricity, because the ions can move freely and can conduct electrical energy.

From this point of view, the combination of sodium and fluorine forms an ionic compound. This is the basic law of chemistry. It is of great significance to explore the composition and properties of substances.