Examine the ball-and-stick model of valine below. Identify the carboxyl group, the amino group, and the R group.
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Question

Examine the ball-and-stick model of valine below. Identify the carboxyl group, the amino group, and the R group.

Accepted Answer

All right. Hi, everyone. So this question is asking us to consider the molecular model of the amino acid Cine shown below. Mark the hydroxyl group, the carboxyl group and the amino group. So let's go ahead and get started. In this case, we have three different functional groups that we have to identify. We have a hydroxyl group or an O group, a carboxyl group or AC double oh and an amino group or an NH two group RNH three if nitrogen happens to be positive. So based on the structure of seine, we know that there are only going to be four different types of atoms present in this molecule, we must have carbon hydrogen nitrogen because of the amino group and oxygen. Now, in this case, recall that there should only be one nitrogen atom in the structure of Cine coming from the amino group. And if I consider the structure of sir in this molecular model, the blue sphere towards the right side of the structure must correspond to the one nitrogen atom that's present in searing because of the amino group. So the first thing I'm going to do here is circle, the blue sphere with two white spheres attached to it to mark it as the amino group. So in this case, the blue sphere is nitrogen and therefore the white spheres attached to the blue sphere must be hydrogen. Now recall also that all amino acids have the same general structure in which the amino and carboxyl groups are connecting to the same alpha carbon. So considering once again, the structure of searing, the blue sphere which represents nitrogen is connected to a gray sphere in the center of the model. This means that the gray sphere or all gray spheres should represent carbon. All of the gray spheres here represent carbon. And if I consider the carbon atom on the top left side of the structure, I've got one carbon atom attaching to two red spheres. Now one of the red spheres is actually double bonded to this gray sphere right to this carbon atom. Whereas the other red sphere is single bonded to carbon and has an additional white sphere for hydrogen. This means that on the top left side of the structure is the carboxy group because the red spheres must therefore be oxygen. Because in this case, the double bond between carbon and the red sphere would represent the car bal and the single bond between carbon and the other red sphere would represent the hydroxy group attaching to the carbon, right. So on the top left side of the structure is the Car boxer group, which therefore confirms that the R spheres represent oxygen in this model, which means that we only have one group left to identify, which is the hydroxyl group. Now, if we look at the bottom of this model itself, we can see that we have one more red sphere that is attached to a white sphere which represents hydrogen. So therefore, on the bottom of the structure must be the hydroxyl group because that would be our O group and there you have it. So on the top left side is the carboxy group. On the top right is the amino group and on the bottom of the structure is the hydroxyl group. And so with that being said, thank you so very much for watching and I hope you found this helpful.

Examine the ball-and-stick model of valine below. Identify the carboxyl group, the amino group, and the R group.
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Verified video answer for a similar problem:

Key Concepts

Carboxyl Group

Amino Group

R Group (Side Chain)

Examine the ball-and-stick model of valine below. Identify the carboxyl group, the amino group, and the R group.<IMAGE>

Verified video answer for a similar problem:

Key Concepts

Carboxyl Group

Amino Group

R Group (Side Chain)

Examine the ball-and-stick model of valine below. Identify the carboxyl group, the amino group, and the R group.
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