Why is knowing the number of valence electrons important in chemical bonding?

Knowing the for chemical is pivotal! such as Na has a charge of +1 as you look on since it is more likely to lose an electron than gain 7 electrons to reach full octet. While Cl has a charge of -1 in which it is more likely to gain an electron than losing 7 electrons to become 7+. So When you do a chemical bond bewteen Na and Cl you get NaCl. The +1 charge on Na cancels out the -1 charge on Cl in which NaCl is stable with a charge of 0. A different example would be H which has a charge of +1 and oxygen with a charge of -2. Here when you bond these two ## H^+1 + O^-2 --> H^2 O)## . Here by knowing the charge of each element you know how many hydrogens you need to make water. allows you to know how much of an element you need to bond with another element based on its charge.