This video shows the "reactivity" of the Halogens (F, Cl, Br, and I). Pay attention to the difference in reactivity....(note the Brits use prefixes when naming Ionic Compounds....that's a no no)
There is a link to the main Nomenclature (chem-speak for Naming things) Tutorial under the study resources tab. This resource is massive so I have placed specific links found on that sight below to make it easier to navigate. Each link below can be found in the larger Nomenclature tutorial.