How do the number of electrons in an energy level affect bond formation?

Concept:

When an atom has incomplete number of electron in its outermost orbit then it has great tendency to react with another atom which satisfies their octate either by sharing or by transferring their electrons. The involved electrons are called valence electrons. These electrons will effect the energy level because of the transition of these electrons from one energy level to another energy level.  

In case of electrovalent compound, the valance electron complete their octate by transferring their valence electrons while in the covalent compound, they complete their octate by the sharing of their valence electrons.

Hence, the valence electron of the atom effect the energy levels by the transition from one state to another state in the bond formation.

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2

the objects have the same charge.