Which group on the periodic table would have zero electronegativity because they have a full octet?

-inert or noble gases
-alkaline earth metals
-alkali metals
-halogens

Ahelium balloon contains 16.9 l of helium at stp. how many atoms of helium are in the balloon

Which factor is likely to impact the possible number of compounds? presence of unlimited number of elements in the periodic table the inability of atoms to align perfectly with other atoms the ability of all elements to react with every other element all elements being equally reactive

Can anyone answer these questions? ? i need it before 1: 00pm today