Which of the following elements does not form a monatomic ion?

Helium

Explanation:

Hi, Helium is the only one in that list that belongs to the noble gases (group 18 of the periodic table).

This gases have the characteristic of being stable in a monoatomic molecule

Why? Becuase they have their last atomic level with a completed octet of electrons and cause of that, they don't have the need to gain, lose or share electrons with other atoms.

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.

2b2t

explanation:

2b2t