group 7 - halogens group 8 - noble gases
The combining ratio for Group II elements with Group VII elements is 1:2. For example, calcium (Group II) will combine with chlorine (Group VII) to form calcium chloride with a ratio of 1 calcium atom to 2 chlorine atoms.
Group VII and Group 8 ( the noble gases)
Group VII, the Nitrogen Family
Group VII A or XVII or Halogens.
Column VII A is an obsolete name; the official name of IUPAC is Group 17 (halogens group).
The elements in group VII of the periodic table are known as the halogens. This group includes fluorine, chlorine, bromine, iodine, and astatine. Halogens are highly reactive nonmetals that readily form salts with metals.
It is because they are halogens
Chlorine- Group VII- It has 7 valence electrons Group VII A- It does not lose electrons from its penultimate shell. Period 3- It has 17 electrons, therefore, electronic configuration is 2,8,7...3 shells
Bromine belongs to Halogens, vii A group of periodic table.
These obtained compounds are halides, ionic compounds.
Francium and Fluorine. They would react instantaneously and explosively. However, this would never be done in an open lab. , because francium is radio-active. However, Sodium (Grp (I)) and Chlorine (Grp(VII)), will react in a gas jar in the lab. But less vigorously than the above two.