Use lewis dot symbols to show the sharing of electrons between a nitrogen atom and fluorine atoms to form a molecule in which each atom has an octet of electrons.

Explanation:

Lewis dot structure is the representation of the valence electrons around the atom of an element. it also shows the number of unpaired electrons present in a molecule.

Nitrogen has atomic number of 7 and electronic configuration is given as:

Fluorine has atomic number of 9 and electronic configuration is given as:

Since fluorine is highly electronegative atom.will attract electrons of nitrogen towards itself.So in Lewis dot structure the fluorine atom will present around single nitrogen atom.

The Lewis structure is given in an image attached.

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).