How is sodium chloride formed (Nacl)?

1: One electron transfer from sodium atom to chlorine atom. sodium atom has 1 electeon in its outermost shell .
2: after losing one electron sodium atom becomes sodium ion (Na⁺) . the chlorine atom gains one electron to become chloride ion (cl^-)
Negetive  asnd positive ions attract each other to form sodium chloride (Nacl)
Thr valency of rach element shows the number of electrons that the atom releasea or gains . find the number of electrons released or gained for each element.