* Francium is in group 1 of the periodic table, making it an alkali metal. Alkali metals have a tendency to lose one electron to achieve a stable electron configuration.

* Fluorine is in group 17 of the periodic table, making it a halogen. Halogens have a strong tendency to gain one electron to achieve a stable electron configuration.

When francium and fluorine react, francium will lose an electron (becoming a positively charged ion, Fr+) and fluorine will gain that electron (becoming a negatively charged ion, F-). These oppositely charged ions will then attract each other electrostatically, forming an ionic bond.

The resulting compound would be francium fluoride (FrF).