Jason combines the two intermediate steps shown. 2 equations. First: upper N subscript 2 (g) plus upper O subscript 2 (g) right arrow 2 upper N upper O (g). Second: 2 upper N upper O (g) plus upper O subscript 2 (g) right arrow 2 upper N upper O subscript 2 (g). Which best describes what Jason should do with the oxygen molecules?

The molecules of oxygen should be placed as reactants in the equation.

Explanation:

1:      N₂ + O₂ → 2NO

2:     2NO + O₂ → 2NO₂

complete reaction:

N₂ + 2O₂ → 2NO₂

We can not place oxygen at the side of products neither we can cancel it because, products can only be obtained at the end of the reaction but according to the equations' oxygen is not the end product of the reaction. But the addition into the reaction (Eq. 2) to make the new product.

Also, we can not cancel it because to cancel out molecules of oxygen should be present at the both sides with same amount in the stoichiometric equation.

Hence, in a balanced chemical equation, oxygen should be written as a reactant by using the correct number of moles.

i believe it is-

d.) gravity pulled particles of dust and gas together to form planets.