Jason combines the two intermediate steps shown.

[tex]\[
\begin{array}{l}
N_2(g) + O_2(g) \longrightarrow 2 NO(g) \\
2 NO(g) + O_2(g) \longrightarrow 2 NO_2(g)
\end{array}
\][/tex]

Which best describes what Jason should do with the oxygen molecules?

A. Place two of them as products.
B. Place two of them as reactants.
C. Cancel them out because there is one in each equation.
D. Double them because there is one in each equation.



Answer :

To solve this problem, we need to analyze the two given chemical reactions and determine how to combine them while accounting for the oxygen molecules ([tex]\(O_2\)[/tex]) correctly.

The two given reactions are:

1. [tex]\(N_2(g) + O_2(g) \longrightarrow 2 NO(g)\)[/tex]
2. [tex]\(2 NO(g) + O_2(g) \longrightarrow 2 NO_2(g)\)[/tex]

We aim to combine these reactions step-by-step, ensuring the oxygen molecules are treated correctly.

Step 1: Analyze the individual reactions.
- In the first reaction, [tex]\(O_2(g)\)[/tex] is a reactant.
- In the second reaction, [tex]\(O_2(g)\)[/tex] is again a reactant.

Step 2: Combine the reactions to form a single overall reaction.
Since we are adding these reactions together, let's sum up all the reactants and products:

Reactants:
- From the first reaction: [tex]\(N_2(g) + O_2(g)\)[/tex]
- From the second reaction: [tex]\(2 NO(g) + O_2(g)\)[/tex]

Products:
- From the first reaction: [tex]\(2 NO(g)\)[/tex]
- From the second reaction: [tex]\(2 NO_2(g)\)[/tex]

When we add the two reactions, we see that the intermediate [tex]\(2 NO(g)\)[/tex] appears on both sides of the equation (as a product in the first reaction and a reactant in the second reaction). These cancel each other out:

[tex]\[ \begin{align*} N_2(g) + O_2(g) &\longrightarrow 2 NO(g) \\ 2 NO(g) + O_2(g) &\longrightarrow 2 NO_2(g) \end{align*} \][/tex]

Result after canceling [tex]\(2 NO(g)\)[/tex]:

[tex]\[ N_2(g) + O_2(g) + O_2(g) \longrightarrow 2 NO_2(g) \][/tex]

Step 3: Simplify the overall reaction:
Combine the [tex]\(O_2(g)\)[/tex] molecules on the reactant side:

[tex]\[ N_2(g) + 2 O_2(g) \longrightarrow 2 NO_2(g) \][/tex]

Thus, the correct procedure is to double the oxygen molecules ([tex]\(O_2\)[/tex]) because there is one in each equation initially, and when combining the reactions, we add them together to balance the entire equation accurately.

So, the best description of what Jason should do with the oxygen molecules is:

Double them because there is one in each equation.