Hello from Chem Help ASAP. We’re going to talk about high oxidation state
functional groups. Of course, we’re referring to the oxidation
state of carbon. All these functional groups are going to have
four bonds from a more electronegative atom to carbon. That’s going to be our theme. As it turns out, once we get to this high
oxidation state, all four of our bonds to carbon are electronegative atoms, which means
we don’t have a carbon-carbon bond. So, we won’t see these functional groups in
our molecules very often, but sometimes we will. It’s worthwhile knowing just to complete our
series. The first molecule I want to talk about is
this one. This is called carbon dioxide – obviously
an important molecule. Notice that that carbon has four bonds to
a more electronegative atom. Another molecule that you’ve probably heard
of before is this one. It has biological relevance. This is urea. It’s part of how you body processes nitrogen,
and it stores nitrogen to be excreted in urine. So urea is another… Ureas all have that central carbon, which
has four bonds to more electronegative atoms. Two bonds to oxygen. Two to two different nitrogens. I’m going to show a series of compounds at
the bottom. It turns out, when CO2 interacts with water,
it forms something called carbonic acid. CO2 and water mix in the ocean, so you form
carbonic acid in the water. Carbonic acid can be deprotonated to form
the bicarbonate anion. Furthermore, it’s possible to deprotonate
this again and form the carbonate dianion. This is part of the buffering system of seawater. This plays a big role in the carbon cycle
of the globe – how water is buffered, the ocean water is buffered. How oceans can absorb CO2 and release CO2. So, high oxidation state carbon functional
groups are extremely important. From a synthetic organic chemistry standpoint,
we won’t see them very much. But, they are absolutely out there, and they
play a big role in things like biology as well as the environment.