Explain in words or using your diagrams how beryllium atoms would react with fluorine atoms. Show clearly the outcome of the reaction and state the formula.

Explanation:

To delineate the the nature of the bonds that would be formed between the two elements, let us first write the electronic configuration of the two species;

  Be  = 2, 2

  F  = 2, 7

 Beryllium is a metal with two valence electrons whereas fluorine is a halogen with seven valence electrons.

When Be loses two electrons it becomes isoelectronic with He;

                 Be →  Be²⁺ + 2e⁻  

Also, when fluorine gains  an electron, it becomes isoelectronic with Ne;

               F  + e⁻ →  F⁻

This loss and gain of electrons between the two elements creates an electrostatic attraction them and they enter into an electrovalent bond.

      Hence;

           Be²⁺  + 2F⁻ → BeF₂