Other contributors have said "What are the key facts for group 7 on the periodic table?" is the same question as "What are the facts for group 7 on the periodic table?" If you believe that these are not asking the same thing and should be answered differently, click here
What are the facts for group 7 on the periodic table?
known as the halogens, exist as discrete, diatomic molecules. Highly reactive elements. Flourine is the most electronegative element. Flourine and chlorine exist as gases, bromine as a liquid and iodine as a solid.
Group seven begins with Manganese. Other elements in the group are: Technetium, Rhenium, and Bohruim. All of these have been classified at metallic substances.
If I had to guess I'd say it has something to do with maybe gasses an/or lights.(just a guess)
here is some info I found though.....
http://en.wikipedia.org/wiki/Group_7_element
A Group 7...