Question

Question #7792a

Answer 1

I'll try and interpret the question correctly...

Explanation:

The first question is why nitrogen dioxide is `"NO"_2` (I believe).

This comes from the nomenclature of nonmetal compounds; for binary covalent compounds such as nitrogen dioxide, they are named such that prefixes are attached to each element ( except if the first element has only `1` of it in the compound, then no prefix is present).

"Nitrogen dioxide" thus means there is one nitrogen present and two oxygen atoms (prefix "di-" indicates `2`), the compound formula is `"NO"_2`.

The next question, I assume, is why the formula is not something else according to the chemical reaction

`"N"_2(g) + "O"_2(g) rarr "NO"_2(g)` (unbalanced)

Here's something worth knowing about chemistry and specifically chemical reactions: reactants can form products that have completely different characteristics than those of the reactants.

The fact that `"N"_2` seems to lose its diatomic property is just the nature of the reaction; although `"N"_2"O"_2` is a real compound, it is far less common to hear about it or work with it.

Basically, the chemical structure of `"NO"_2` is thermodynamically more favorable than that of `"N"_2"O"_2`, and thus the reaction will, under certain conditions, yield `"NO"_2` (you'll learn more about the thermodynamics of reactions later!)

As far as balancing goes, we have so far

• two nitrogens on the left, one on the right

• two oxygens on the left, two on the right

Therefore, nitrogen is the only unbalanced element. To fix this, we simply add a `color(red)(2)` in front of `"NO"_2`:

`"N"_2(g) + "O"_2(g) rarr color(red)(2)"NO"_2(g)` (unbalanced)

Now you may notice that the oxygen quantities have become unbalanced, and there are `4` on the right side and `2` on the left. A quick fix is done by placing another `color(blue)(2` in front of `"O"_2`:

`"N"_2(g) + color(blue)(2)"O"_2(g) rarr color(red)(2)"NO"_2(g)` (balanced)

And our equation is balanced!