Student follow up
The Group 2 elements are known as the alkaline earth metals. They are reactive
metals. Atoms of Group 2 elements lose two electrons to form ions with a 2
charge. Research the reactions of Group 2 elements, then describe and explain
the pattern in reactivity down the group.

Magnesium and calcium belong to the second group i. e. alkaline earth metals. They are known as earth metals because they are extracted from the earth. They are very reactive elements. Their reactivity increases when we go from top to bottom because the outermost electrons goes farther from the nucleus i. e. atomic radius increases so less energy is needed for its removal.

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons