What is the chemical formula of the ionic compound for NaF?

We are aware that the presented substance is an ionic compound in which Na stands for the sodium ion and F for the fluorine ion. The proper name of the compound will be made up of one of them being negative and the other being positive.

Before identifying any chemical substance, let's review the fundamentals; The positive ion, or cation, is called first and is the same as its chemical elemental name. This is one of the main guidelines to be followed when naming any compound. With more electronegative atoms and a smaller anion, sodium will produce the most ionic compound. Sodium fluoride is more ionic than other molecules because fluorine is more electronegative than other atoms and has the lowest size as well.

Because it only needs one more electron to complete an octet and achieve stability, fluorine is more electronegative when combined with other elements. Additionally, as compared to other elements with 7 electrons in the outermost orbit, the valence electrons' distance from the nucleus is the shortest.
The name of the negative ion, or anion, comes last and is completed with the suffix "-ide". According to the aforementioned principles, the name of the given chemical, NaF, can be expressed as Sodium Fluoride since Na will be the positive ion and fluoride will be the negative ion.

So, the name of the compound given will be sodium fluoride.

Hence, option B is correct.