These models show the electron structures of two different nonmetal elements. Element 1 at left has a purple circle at center with 2 concentric black lines around it. The first line has 2 small green balls on it. The second line has 8 small green balls on it. Element 2 at right has a purple center with 5 concentric circles around it, with the first circle innermost. The first circle has 2 small green balls on it, and the second circle has 8 small green balls on it. The third circle has 18 small green balls on it, and the fourth circle has 18 small green balls on it. The fifth circle has 6 small green balls on it.

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.

the complete reaction for the formation of aluminum oxide is as follows;

4al + 3 > 2

so if the molar mass of the is 32.0 g/mol and

so, to form 3.80 mol of

(3.80 mol ) x (3 mol ) x (32.0 g )

dividing by 2 because two moles of will be formed;

∴ 364.8/2   = 182.4g