Which of the following examples best describes a unique functiona...

Question

Which of the following examples best describes a unique functional property of the carboxyl group?

Accepted Answer

Welcome back, everyone. We have a true or false example which states that the carboxyl group is an example of a basic functional group. While the amino group is an example of an acidic functional group. So we're going to begin by recalling upon our Lewis definition of acidity and basic. So for the Lewis definition of acidity recall that that would be expressed as a compound which is a proton or H plus donor. And for Lewis definition of Baity recall that that would be considered a proton or H plus acceptor. So as far as functional groups being a acid or sorry, being acidic or basic, we would need to determine whether the functional group performs according to our Lewis definition for acidity or basis acidity. So let's begin with considering the carboxyl group for the carboxyl group recall that we utilize the condensed shorthand as coo H in which we have an alkyl chain or our group, we say methyl, which is bonded to a carbonyl carbon, which has a double bond to oxygen. And that carbonyl carbon is also bonded to a hydroxyl group or O H. So let's recognize that overall, we can say we have R coo H where R represents our alkie chain. Now, we can observe that we have hydrogen atoms within our methyl group where three are implied as bonds to carbon. And we also have a hydrogen atom bonded to oxygen in our hydroxyl group. Now, due to the fact that we can perform resonance with the double bond in our Carboni group where we can move the double bond as electrons or alone pair of electrons on our oxygen in the Carboni, which can also overall create an electron withdrawing effect. So we can say that we have an electron withdrawing group, which is our carbonyl group because of that highly electron negative oxygen, once we add more lone pairs from the double bond in our carbon and transfer them as a lone pair to oxygen. This is going to create an electron withdrawing effect in our structure overall for our carboxyl group. And thus the carbon oxygen bonds within our carbon bonded to hydroxyl is going to be more strong than the oxygen hydrogen bond in our hydroxyl group. Thus, this creates a weakened hydroxyl group because we have that electron withdrawing effect of our carbonyl group. And because we have a weakened hydroxyl group, we have a proton available for donation. And thus, we can say that carboxy is aesthetic. So we can observe that if we have our carboxyl group, R coo h reacting with water, we would donate a proton to water where water is the base being our proton acceptor. And on the product side, in this acid based neutralization reaction, we would form the conjugate acid or sorry, the conjugate base correction of carboxyl, which would be R coo with a minus one charge since we moved electrons to oxygen. And we would also have our second product hydro num, which is our conjugate acid of water. So we would correct the first part of our prompt to say that the carboxyl group is an example of an acidic functional group. And now let's see if what the prompt states for an amino group is correct. So for an amino group recall that we have an alch chain, so we'll just use E or ethyl rather C H three C H two, that ethyl group is then bonded to an amino group or nitrogen which has two bonds to hydrogen and then a lone pair on itself based on nitrogen's bonding preference of having three bonds and one lone pair on itself. So for our amino group, we can say that it's condensed form would be R N H two where R represents our alch chain and N H two represents the amino portion. And overall, this functional group is an aiming. So we're going to observe whether we have an opportunity of accepting any protons due to the fact that we have an available lone pair on nitrogen, as well as the lack of any electron withdrawing groups, this nitrogen or this lone peron nitrogen is capable of accepting a proton and forming a third bond to hydrogen. And thus, our, I mean group is going to be a base since it will accept a proton. Thus, we can write out an equation where we have our amine R and H two react with water. A base which will form as a product because our water is going to act as an acid. In this case, instead of a base, water will donate a proton to our amine. And we would form as a result R N H three where now nitrogen has a plus one charge since the two electrons were used to form a bond to the third proton. And then this would be the conjugate acid of our base, which is our, I mean, where we would then form the conjugate base of our acid water being hydroxide. And overall going back to our given statement in the prompt, we would correct the second portion of our statement which states that the amino group is an example of a basic functional group is how we would correct it. So, since we had to make corrections to our given statement in the prompt, we would confirm that our final answer is going to be that the given statement is a false statement. So I hope this makes sense and let us know if you have any questions.

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Which of the following examples best describes a unique functional property of the carboxyl group?

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