# Video: Identifying the Structural Formula of Nitrous Oxide

Nitrous oxide (N₂O), commonly known as laughing gas, is used as an anesthetic in minor surgeries, such as the routine extraction of wisdom teeth. Including lone pairs, give the structural formula of nitrous oxide.

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### Video Transcript

Nitrous oxide, N2O, commonly known as laughing gas, is used as an anesthetic in minor surgeries, such as the routine extraction of wisdom teeth. Including lone pairs, give the structural formula of nitrous oxide.

Our first step will be to determine the number of valence electrons in nitrous oxide. We can determine the number of valence electrons for each atom by using the periodic table. Nitrogen has five valence electrons. And there’s two nitrogens in nitrous oxide. And oxygen has six valence electrons. This gives us a total of 16 valence electrons.

The next step is to place the atoms and connect them with single bonds. The atom that we put in the center should have the most sites available for bonding. In general, this will be the atom that has the lowest number of valence electrons because it has more electrons needed to fill its outer shell. This means that we should put one of the nitrogens in the center.

The next step is to distribute the remaining electrons so each atom has a full octet, or eight electrons, starting with the terminal atoms, or the atoms that are on the outside of the structure. Each single bond contains two electrons, one from each atom participating in the bond. So we have four electrons already drawn in our structure, meaning that we have 12 electrons remaining to distribute.

If we distribute the 12 remaining electrons to the outside atoms first, we’ll run out of electrons before the nitrogen in the center has a complete octet. If this happens, we can form multiple bonds between the atoms by removing a lone pair on one of the atoms that already has a full octet. So we can remove one of the lone pairs from the oxygen and put a double bond between the nitrogen and the oxygen.

But nitrogen still doesn’t have a full octet, so let’s do the same thing to the other nitrogen. Now, we’ve removed a lone pair from the nitrogen to create a double bond between the nitrogen and the nitrogen. Now, each atom in our structure contains a full octet. So this is the structural formula of nitrous oxide, including its lone pairs.