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Help organic chem question

Help I don’t know which answer is correct!!
Is the molecule is heated with NaOH ( aq)
It would be base hydrolysis so the part of the answer I circled red the (OH) part I did this question again and instead of that part I got NaO because when the ester splits the double bond oxygen isn’t bonded to the O part and therefore it can’t gain an OH it has to gain an ONa right??
018C0291-E8C1-4648-93AF-934D07DC6045.jpeg
F50C37CE-218A-48A5-898C-58A14E284B96.jpeg
And also do you add 2NaOH for the hydrolysis of this molecule???
(edited 1 year ago)
Original post by Alevelhelp.1
Help I don’t know which answer is correct!!
Is the molecule is heated with NaOH ( aq)
It would be base hydrolysis so the part of the answer I circled red the (OH) part I did this question again and instead of that part I got NaO because when the ester splits the double bond oxygen isn’t bonded to the O part and therefore it can’t gain an OH it has to gain an ONa right??
018C0291-E8C1-4648-93AF-934D07DC6045.jpeg
F50C37CE-218A-48A5-898C-58A14E284B96.jpeg
And also do you add 2NaOH for the hydrolysis of this molecule???


Okay. the one with the benzene ring doesn’t have an Na - the Na would be part of the carboxylic acid group - that benzene ring doesn’t have a carboxylic acid group because it is phenol. The other two are correct though.

Tip: in base hydrolysis, what would’ve been the COOH group would always be COONa or COOK (if KOH was used) and the alcohol group would always be -OH.
9F6C3690-E04A-4FEE-9F21-1933C1A68EA3.jpg.jpeg

Here’s a better explanation (visual)
Original post by JA03
9F6C3690-E04A-4FEE-9F21-1933C1A68EA3.jpg.jpeg

Here’s a better explanation (visual)


Thanks! You know for the phenol part I replaced the OH with NaOH because my teacher said the phenol can react further with NaOH to give the thing I drew. Is that correct and also why are two molecules of NaOH used??
Original post by Alevelhelp.1
Thanks! You know for the phenol part I replaced the OH with NaOH because my teacher said the phenol can react further with NaOH to give the thing I drew. Is that correct and also why are two molecules of NaOH used??

It can be because phenol is a weak acid but this is slightly confusing given that in this esterification the phenol is an alcohol as opposed to an acid.

Phenol bonded to a carboxylic acid means that in hydrolysis, it acts as an alcohol. so it would have an OH instead of ONa. You get what I'm saying?

If the phenol was bonded to another alcohol then yeah it would be ONa as in that case it probably would've gotten rid of the whole OH but in this case, it didn't. I will get a second opinion from someone that is VERY good at chemistry if it still is confusing.
Original post by Alevelhelp.1
Help I don’t know which answer is correct!!
Is the molecule is heated with NaOH ( aq)
It would be base hydrolysis so the part of the answer I circled red the (OH) part I did this question again and instead of that part I got NaO because when the ester splits the double bond oxygen isn’t bonded to the O part and therefore it can’t gain an OH it has to gain an ONa right??
018C0291-E8C1-4648-93AF-934D07DC6045.jpeg
F50C37CE-218A-48A5-898C-58A14E284B96.jpeg
And also do you add 2NaOH for the hydrolysis of this molecule???


Look at your balanced equation. In the second photo you have 2NaOH (hence 2 sodiums) but in the product you have 3 sodiums.
Original post by JA03
It can be because phenol is a weak acid but this is slightly confusing given that in this esterification the phenol is an alcohol as opposed to an acid.

Phenol bonded to a carboxylic acid means that in hydrolysis, it acts as an alcohol. so it would have an OH instead of ONa. You get what I'm saying?

If the phenol was bonded to another alcohol then yeah it would be ONa as in that case it probably would've gotten rid of the whole OH but in this case, it didn't. I will get a second opinion from someone that is VERY good at chemistry if it still is confusing.


Yeah I’m super confused 😂
Original post by Plantagenet Crown
Look at your balanced equation. In the second photo you have 2NaOH (hence 2 sodiums) but in the product you have 3 sodiums.


This person has 2 responses and they're not sure which one is right because of the phenol bonded to the carboxylic acid.
Okay, desperate times - I hope they're online. @TypicalNerd
Original post by Alevelhelp.1
Yeah I’m super confused 😂
Original post by Alevelhelp.1
Help I don’t know which answer is correct!!
Is the molecule is heated with NaOH ( aq)
It would be base hydrolysis so the part of the answer I circled red the (OH) part I did this question again and instead of that part I got NaO because when the ester splits the double bond oxygen isn’t bonded to the O part and therefore it can’t gain an OH it has to gain an ONa right??
018C0291-E8C1-4648-93AF-934D07DC6045.jpeg
F50C37CE-218A-48A5-898C-58A14E284B96.jpeg
And also do you add 2NaOH for the hydrolysis of this molecule???


The way you've worded it (gaining an ONa) is strange because ONa is not a nucleophile. Remember that in this kind of hydrolysis the -OH attacks and so initially you do gain an OH, but under basic conditions this OH will then be deprotonated to form the carboxylate which will then form an ionic interaction with the Na+, so it's a 2 step process: addition of OH and then deprotonation.
(edited 1 year ago)
Original post by JA03
This person has 2 responses and they're not sure which one is right because of the phenol bonded to the carboxylic acid.

If you have 2NaOH then I'd definitely say it would be the 2 carboxylic acids that would preferentially be deprotonated to form ONa as their pKa is significantly lower than phenol's. However, I would add an excess of NaOH to hydrolise this molecule and in that case both of the carboxylic acids and the phenol would be in their ONa forms.
(edited 1 year ago)
Original post by Plantagenet Crown
If you have 2NaOH then I'd definitely say it would be the 2 carboxylic acids that would preferentially be deprotonated to form ONa as their pKa is significantly lower than phenol's. However, I would add an excess of NaOH to hydrolise this molecule and in that case both of the carboxylic acids and the phenol would be in their ONa forms.


Thank you everyone!! It means a lot 😀😀😀
I’m revising for my a levels this year I’m so petrified omg 😭😭😭
(edited 1 year ago)
During a base hydrolysis, any product that contains a carboxyl group (COO) will form a salt, so in this case, two salts containing COONa groups will definitely form.

Whether the phenol or sodium phenoxide (C6H5ONa) forms is dependent on the circumstances. The circumstances being related to the moles used or whether your a level specification requires you to know that phenol is acidic.

If you are required to know that phenol is acidic, you may need to consider the mole ratio if it is given. In this case, if the mole ratio is specified to be 1 mole of the starting molecule to 2 moles of NaOH, then phenol should form. If the ratio is 1 mole of the starting molecule to 3 moles of NaOH, sodium phenoxide will form. If no mole ratio is given, assume it is 1 mole of the starting molecule to 3 moles of NaOH.

If you aren’t required to know phenol is acidic, just assume that phenol is produced
(edited 1 year ago)

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