chem reactivity

It has one more electron shell when compared with Mg. Its outermost electron separate from the nucleus further apart than Mg. Its outermost electron experience less attraction force from the nucleus than Mg. It is easier for a Ca to lose its outermost electron than Mg.

Tt is because calcium has more electron than magnesium. Thus, calcium tends to lose electons more actively than magnesium. Hence, calcium is more reactive than magnesium.