Which 2 groups of elements in the periodic table are the most reactive

4 answers

I and VII (or is that XVII?)
alkalis and halogens
My table uses 17 instead of XVII. It would make sense for IUPAC to set a single sytem instead of the three in use.
1. alkali metals and halogens.
2. They have the same number of valence electrons.
3. They usually have high melting points.
4. Low or no reactivity.
5. 17.
@im a npc is 100% correct for connexus!!