3. What identifies an element? the mass number
the atomic number
the atomic mass
the number of neutrons

Atomic number

Explanation: Atomic numbers never change, they stay the same which is why they are what elements are identified by

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.