Intro to Redox Reactions - Video Tutorials & Practice Problems

Identifying Redox Reactions

In this video, we're gonna talk about redox reactions first from a gen C perspective and then from an organic chemistry perspective. Now recall that redox reactions also known as oxidation reduction reactions involve transference of an electron or electrons between reactants. Now, this is our general chemistry definition of a redox reaction in organic chemistry. It's a little bit different here. Redox reactions involve increasing or decreasing the oxygen or hydrant amount on a molecule. Now, when we say oxidation oxidation involves increasing the number of carbon oxygen bonds on the molecule. And if we're talking about reduction, well, that involves increasing the number of carbon hydrogen bonds on the molecule. If we take a look here at oxidation versus reduction, we're gonna see that on the far left side, we have a hydrocarbon in the form of methane. And then on the far right side, we have carbon dioxide here. Notice that they're both grayed out. That's because we don't really deal with these two types of compounds. When we're talking about oxidation versus reduction, we're gonna focus on the middle portion where we're going between an alcohol to what looks like an aldehyde to a carbolic acid that's the portion that we care about in terms of organic chemistry. Now, here we can oxidize a hydrocarbon to our alcohol and notice that we had no carbon oxygen bonds initially. But our first oxidation step creates our first carbon oxygen bond. So this would be for alcohols. If we continue with our oxidation process, we have one carbon oxygen bond. Now we have two because we're double bonded to that oxygen. Now, here I'm showing an aldehyde, but this section here stands for aldehydes and ketones. Now, if we continue with oxidizing this, we get a carbolic acid and we go from being two carbon oxy months and now three. And if we continued further, we get carbon dioxide which has four carbon oxygen bonds. But again, we don't concern ourselves with that portion because that doesn't really um represent an organic molecule for us. Now, going the opposite way we're reducing. We're starting out with the Carboy Acid. We then move over to the alde hyder ketone section here. Notice that we go from three carbon oxygen bonds to now just two and not just that we're increasing the number of carbon hydrogen bonds because here we only had one carbon hydrogen bond and now we're back to two, continue onward again. Now, instead of having two carbon ox um carbon hydrogens, we have three and we're at the alcohol phase. And if we continued on, we have uh four carbon hydrogen bonds. But again, we're not concerned with the extremes. In terms of this image, we don't concern ourselves with hydrocarbons or carbon dioxide. We're operating in the highlighted section in the middle between alcohols, aldehydes and ketones and Carboy acids.

Intro To Redox Reactions Example

Determine if the following reaction represents an oxidation or reduction reaction. If we take a look here, we're gonna say that we have as far as we can see one carbon oxygen bond and we have one carbon hydrogen bond here. Now, here this is just a regular carbon carbon bond and this is just a regular carbon carbon bond. So we don't look at those. Now, we're focusing on this carbon because we can see that it undergoes a change here. That's what we're focusing on it. So we're gonna say here, we're starting out with one carbon oxygen and one carbon hydrogen. If we come over here, what's happened? Well, we can see that this carbon, which is still the same carbon here. It has lost its carbon hydrogen bond. So it has zero of those now. And now instead of being connected to oxygen just once, it's now connected to it twice. So we have increased the number of carbon oxygen bonds. And we know when we do that, that's a sign of oxidation. So here we'd say that this reaction represents an oxidation reaction. We have an alcohol that's been oxidized into a ketone product.

Determine if the following reaction represents an oxidation, reduction or neither.

• A. Oxidation
• B. Reduction
• C. Neither

Determine if the following reaction represents an oxidation, reduction or neither.

• A. Oxidation
• B. Reduction
• C. Neither