Carboxylic acid part 1

Added: 2026-05-18

[00:00:00]now coming to the next chapter that is carboxylic acid carboxylic acid now why do we call carboxylic acid if you see the structure carboxylic acid has this particular structure that is we are having a carbonyl group c double bond o and we are having an o h group carbonyl plus hydroxyl together is called as carboxylic carbonyl c double bond o and this is your hydroxyl oh hydroxyl group together it is called as carboxyl group but that does not mean let me clear it make it clear right from the beginning but that does not mean that carboxylic acid contains properties or causes the properties of both carbonyl group that is aldehydes and ketones as well as of alcohol no not at all not at all we can say that clear just for naming purposes i am saying you that carbonyl plus hydroxide is called as carboxylic acid or carboxyl group we can say that carboxyl carbonate plus hydroxide is called a starbucks silicon and its as a result it is called as carboxylic acid because it releases h plus sign i will show you how it is but that does not mean that it has got the properties it poses the properties of both carbonyl group as well as hydroxyl group no nothing to do with that clear so in this way so what you find is that carboxylic that is acid as you can see the structure it is trigonal planar as you can see it is trigonal planar so this carbon atom is sp2 hybridized this carbon atom is sp2 hybridized as you can see this it is trigonal planar structure the bond angle is here it is 120 degree all right and hence this particular carbon atom is sp2 hybridized carbon atom we can say that clear there is coh group the carbon atom is sp2 hybridized and it is polar in nature all right definitely because it has got two polar group one is carbonyl group another is hydroxyl group so it is much more polar much more polar listen careful this point it is much more polar than aldehydes and ketones as well as alcohols it is much more much more polar in nature with the presence of the two carbonyl group against that and at the same time it also shows resonance we can say that it also shows resonance now how it shows resonance now see here here oxygen definitely four electrons are there this is let us say the structure one now what is what is going to happen this pair of electrons will come here so hence the canonical structure which is being formed is this we can say it is one one two three four five six negative charge and here it is what you can say this particular one you will be having it so here what you find the carbonyl carbon also develops positive charge this is in structure two the carbonyl carbon doubles positive charge your deficiency of electron three bonds are there and this is negative we can say that now what is going to happen from structure 2 what is going to happen this pair of electrons will come here this pair of electron and hence what i am going to get it here that is this particular one and here double bond and this particular one is this now the carbonyl carbon you can see it is neutral the carbonyl carbon in the first what you can say this group and the third group in the first structure in the third structure you can see it is neutral in nature but here the third structure is more comprehensive and much more accepted much more stable in the because it is saying resonance now this is a resonant structure and these are the canonical structure i've done it it shows resonance energy is distributed what resonance means definitely energy is distributed when a particular molecule shows a resonance when a particular structure shows resonance what does it mean energy is distributed and stability increases so here it is more stable in nature so what i want to say is that the third structure is more convincing more stable than any of the structure that is one and two why because here the oxygen atom is negative as well as positive that means energy is distributed equally we can say that so we are having both negative and as well as positive what you can say that is ah oxygen atom energy is distributed audit throughout and as well as the carbon atom is neutral in nature of course it is neutral nature in one structure one also but structure one does not contain the oxygen negative and positive charge negative and positive means what that only makes it highly reactive that only makes it highly reactive it is this too the presence of this negative and positive charge only makes it highly reactive so in this structure it's much much more stable it is much more convincing and it is much more reactive we can say that energy is also completely distributed here in it all right so in this way it process the delocalized electron the electron is also deliberate you can say that the electron deliberates because again this can come here double bond and again this can go here it is single bond it can form so it is again it can be delocalized that means from here we can come back to this structure again from here we can come back to this structure again so hence it is resonance we can say that energy is distributed thoroughly but it is more stable more convincing and more reactive in nature we can say and also it shows it is more polar in nature you can see that polarity is well defined here in this particular structure negative as well as positive force both are being there that is well defined in this particular structure for that reason i said this structure is more convincing in nature now what i find is that this is about the structure of carboxyl group i was explaining you now coming to the acids now if i put here h atom if i put h atom here then what will i get i will get formic acid hcoh if i put ch3 atom i will get ch3 group then i'll be putting and then i'll be getting ch3coh now this is called formic acid now formic acid is a common name iupac name is methanoic acid methanoic m e m m ipc names why methanol because one carbon atom myth and it is carbon single bond on and secondary suffix is weak acid so methanoic acid similarly this is what ethanolic acid or acetic acid now as i was saying you formic acid the name it has come from the word we can say that ah forum we can say which is nothing but and we can say and so hence we get this particular formic acid from the bites or the from the sting of the ants and the mass when the ants and the mass they sting sooner that bites you so that is an irritations is there and itching is there it becomes red and also it burns we can say the burning sensation is there that is nothing but it leaves in the stings of the ants and the vast formic acid there and that it leaves in your body but due to which this itching and this burning sensation or this whatever you can say irritations has been taking place from there that is from the word that is for mick or foreign or for my we can say we have got the word formic acid all right similarly ethanolic acid has ethanic acid is also called as vinegar vinegar or acetic acid is also called as acetic acid or vinegar as that is acid acid means what vinegar we can see that from there we got it similarly in this way many names are there like butaric acid from butter tartaric acid from tamarind we can say that clear malic acid from apples we can say clear in this way these are the sources of different what you can say carboxylic acid some of the sources i told you that is buttery can say we are getting it from butter there is butaram becomes that clear formic acid we are getting it from the ah ants i said you that is that is that the lattice name is formic or form for my or it is for mikka or whatever you can say that the different c the naming is uh according to different ages the name has changed slightly got it initially we are known as for my formica then for my then for in this way the name has changed whatever it is ultimately it is called as formic acid which has come from the ants and the vas from there we have got the name just to remember it all right similarly acetic acid we have come from the word acita means vinegar right that's a source that is hence it is also called as vinegar we can say that clay similarly uh butaric acid that is deutera means butter we can say that malic acid we are getting from apples we are getting tartaric acid from tamarind in this way olic acid from tomatoes in this way so many are there we can say that clear fine so in this way uh we get the name of the this is the common name as well as the iupac name i studied okay now more of the iepc name i'm going to come to it more of the iep so now the first is that is the carboxylic acid is represented by the general formula rcoh right the general formula of carboxylic acid is r c o o h this is general formula of carboxylic acid so to say that r is any alkyl group just now i have discussed with you some of we can say that so we have got if h is there then formic acid or methanolic acid if ch3 is there the carbonic acid if ch3 ch2 is there then propanoic acid then if ch3 ch2 ch2 coh is there then we can say butanoic acid in this so it goes on or butyric acid the common name is we can say that for the butanoic acid we are having it in this way now the what you can say this saturated monocarboxylic acid containing that is only the carbonyl group are also called as fatty acids they are known as fatty acids because these are usually used to make the fats got it there is the higher members of the aliphatic carboxylic acid okay what i said saturated that is monocarboxylic acid containing only the carbonyl sorry carbonyl i'm saying carboxyl group i'm very sorry it's not carbonyl containing only the carboxyl group are also called fatty acids but which which which are higher carboxylic acids higher means containing 12 to 18 carbon atom present in it containing mainly 12 to 18 carbon atom present in it because they are the source of the fats we can say that they are basically solids that is in occurs in natural fats and easters this particular assets all right 12 to 18 carbon atoms the carboxylic acids basically occurs in natural fats and esters i said use the source of the fats that is it can be obtained that is fats can be obtained easters can be obtained by hydrolysis of this particular assets we can say that okay so hence it is also called as fatty acids those carboxylic acids that is higher carboxylic acid we can say that got it now similarly if it is aromatic acid then it will be a o o h if it is aromatic acid we can say that a r means any aryl group like c 6 h 5 c o o h it is called as benzoic acid benzoic acid means i mean to say this one if i draw the structure then this is your benzoic acid why is benzoic because i said you benzene ring attached to carbon atom is called as benzo benzene ring attached to carbon atom is called as benzo benzene ring attached to ch is benzal benzene ring attached to ch2 is benzyl all right i've told all those things so benzo plus oe acid is called as what benzoic acid we can say that similarly if you are having that is a ch3 group attached here ch3 with the benzene ring we are having ch3 group attached to it and we are having cooh what is this known as now benzene ring ch3 is solvent and olic acid is acid rather i should say ortho because in ortho position it is there one two or two you can see all right that is one two which is orthosis orthotalvic acid or the iupac name is nothing but it is known as methyl benzoic acid two methyl this is one this is one and this is two of course because functional group is first first carbonator so two methyl benzoic acid we can say that clear that similarly we can also have this particular compound now we can have many understood many compound we can have it like ch2cooh ch2ch it is called as phenyl what you can say acetic acid phenyl how it is finite and two carbon is there so it is phenyl ethanoic acid or phenyl acetic acid see this c6h5 this benzene ring is your finite from benzene ring if you remove one hydrogen then only you will be adding this particular group now so if you remove a hydrogen from benzene ring what is that called as finale since it is called phenyl and this is acetic acid or iupac name is phenyl ethanoic acid two carbon is there it for that particular reason carbon carbon single bond is on and co h is we cancel so phenyl ethanoic acid we can say that clear in this way we can have monocarboxylic acid monocarboxylic acid means all this one which is talking to all this all this in aliphatic aromatic whatever i told you the formula all contains you can see is one coh group all these particular formula which i said which i discussed with you just now so all this contains one coh group so one coh groups group means it is known as monocarboxylic acid if if it contains one co group whether it is aliphatic or whether it is aromatic got it if it contains now if it contains two coh group two for example here it is you can see coh single bond co h what is this known as it is known as nothing but ethane one two dioic acid two carbon heat single bond n ethane one two one two diolic acid oxalic acid you know it definitely ch2cooh this is also dicarboxylic acid what is known as melonic acid this is called malonic acid alright then we are having ch2 coh now this name you need to remember it understood for that reason i am writing it this name you have to remember it basically the common name ibiza is not difficult at all it's not difficult like this one what is it one two three three carbon atom propane one two dioic acid finished hydration is so easy one two three prop single bond n propane one two dioec acid first and one three sorry propane one three diode acid one three it is not one two one three dioic acid similarly what is that one two three four so butane one four diabolic acid but the common name is succinic acid name i don't think success you need to remember you have to understand it there is success similarly if you have ch2 ch2 c o o h we can say that again c h 2 c h 2 o what is that it is nothing but known as adepic acid it is called adepic acid similarly ch2 ch2co and cs26 adipic acid but similarly we are also having that is in case of aromatic suppose first and second i am taking this as first and this is second this is first second we can say or for second photo so it is known as phthalic acid spelling is ph h h a l i c phthalic acid we can say that now first and second if it is there it is called a phthalic acid if first and third coh group is there listen carefully first and third this first and second is so first and third is there it is called as isophthalic acid isothermic iso i see iso phthalac if it is first and third one and three now if it is one and four here the co group will come here first and fourth it is known as perithelic acid t e r e p h t h a l i c terephthalic acid it is a first and fourth c h group is there along with the benzene ring which is called terephthalic acid or iep what you can say benzene one for dioic acid you can say that yeah so in this way this is about your that is uh dicarboxylic acid having cooh twice all right now we will come to tricarboxylic acid try having three coh group present in it we can say that now see here ch2cooh similarly c h c o o h similarly c h two c o h it is called as dry carbo lily acid try carbilic acid we can say that try karba lillic acid now very simple it is i'll remove this h and instead of that i'll put it here h all right just i'll remove this edge and instead of that i'll just put it which you know what is the name it is very common it is found in lemons this acid is found in lemons what is that citric acid that is citric acid responding lemons so this is a formula citric acid which comes under tricarboxylic acid we can say that in this way many more name you can have it so in your chapter in the beginning of the chapter you can see that is the iupac name the common name a chart is given for both aliphatic and aromatic which i discussed with you you please do it this particular but you can say the chart you learn it that particular common names i recently no need to learn it all because iep's name is always guided by rules and if you remember the rules you need to learn the ipc name and you can't learn it also it is better to learn the common names we can say that clear so the higher fatty acids are called as uh palmitic acid is the only acid is the steric acid is there steric acid is what c17h35 steric acid similarly we have got palmitic acid it is nothing but c uh what you can say 15 h 31 c o h we can say that clear so in this way what what you find is that we are having the higher carboxylic acid which i have discussed with you which is known as fatty acids we can say that similarly in uh carboxylic in what you can say aromatic acid we have also got phthalic acid apart from that we are also having that is cinnamic acid cinnamic acid i have discussed in not in this chapter in other chapters i've discussed with you ceramic acid ch double bond ch single bond c o o h is called as cinnamic acid we can say apart from phthalic acid we have also got a very important one this one is cinnamic acid so to say all right clear so this is all about your iupac and the common name the structure of carboxylic acid the resonance structure which is more stable whether it's polar or not it is highly polar i have said you alright all these things were discussed about the carboxylic acid so to say now it is a very reactive group and why it is acid that's very important now thing is white is acid now see here c o o h all right c o h fine so here the lone pair of electrons is there what will happen now oxygen is more electronegative than hydrogen you know that all right now oxygen will have always have a tendency but it will always have a tendency to what you can say take the pair of electrons from etch atom to take the pair of electrons from this particular h of them always have a tendency because oxygen is more electronegative than hydrogen so when this pair of electrons would be taken by oxygen then what will happen we will have co this is there then this this this this this and this negative charge because you do excess of electron negative charge and due to deficiency h plus sine is released we can say because the cleavage of the bond takes place cleavage of the bond takes place and hence h plus sin is released you can say that due to the release of h plus signs we say carboxylic acid is acidic in nature so why this particular group we call it as acid because it releases h plus sine we can say that how in this way it releases now if any particular group is there which is an electron withdrawing group it will withdraw electron from carbon carbon will electron withdraw from oxygen an oxygen with electron redraw will withdraw electron from hydrogen and hence the cleavage will takes place easily remember it if an electron withdrawing group is present here electron withdrawing group then the acidic character is going to increase why because this is going to be draw electron carbon carbon from oxygen oxygen from hydrogen and hence the cleavage takes place easily here and due to which x plus sign is also readily released all right so electron withdrawing group means for example suppose an no2 group is attached for example suppose we are having an hcl group attached they are the electron withdrawing group correct halogens are attached here and neutral group is attached here cn is attached here mainly multiple bonds and halogens they are the electron withdrawing group so if it is attached here it will increase the what you can say acidic character but suppose if i use here an alkyl group like ch3c2h5 it will decrease the acidic character but it for that particular reason remember it formic acid hcooh now forming h atom is neither donor nor white line is right so formic acid listen carefully is more acidic than acetic acid because in formic acid h atom is there in acetic acid what it will be ch3 group will be there and ch3 is a donor group donor means it will donate to this carbon now will this carbon atom withdraw electron oxygen will the oxygen at a vitro electron from hydrogen no with difficulty it will be drop but with difficulty compared to this formic acid compared to this suppose if i use here ch3 then acidic character is going to decrease compared to formic acid why because this is an electron what is that donor group it will donate to this carbon this carbon will donate to this particular oxygen so will oxygen atom readily withdraw electrons from hydrogen no it will but it will not readily withdraw electron from hydrogen due to which acidic character decreases so hence formic acid is very strong acid compared to acetic acid compared to propanic acid compared to butanoic acid means as the alkyl group goes on increasing acidity character decreases because as plus i effect alkyl group goes on increasing means carbon atom goes on increasing plus i goes on increasing as plus i effect increases as the character decreases all right so this you need to remember it in this way we can say that that carboxylic acid is more acidic in nature and moreover moreover what you find is that here that is what you find here this particular structure in the reactant side and here we are having this structure in the product side now this is more resonant stabilized this particular one then this particular structure we consider this is stabilized due to resonance more so hence equilibrium always favors in the forward direction all right if you ask me that out of this two structure which is more stable then this is more stable why because it is stable due to resonance how it is stable due to illusion resonance because this negative charge is equally distributed throughout this particular what you can say oxygen this and this oxygen you do it this oxygen is also slightly electronegative del minus and this also is slightly del minus then at that time how you sow the structure you will show the structure the diagram in this way in this way you will show it this means that is the negative charges is equally distributed throughout the two oxygen atom all right due to which what we find is that that this structure as negative charges is equally distributed that means it is delocalized and i've said you always whenever you are delocalizing the charges that means you are distributing the energy as you are distributing the energy less energy is remaining in the compound if less energy is remaining in the compound the compound is more stable in nature so hence it is more stable due to resonance compared to this as it is more stable the equilibrium is favored in forward direction as equilibrium is favored in forward direction h plus n is readily released due to this reason due to this reason this structure is more stable and edgeless and is readily released and hence carboxylic acid is more acidic in nature got it carboxylic acid is more acidic in nature due to this reason also carboxylic acid because there are many compounds there like in alcohol you've seen also seen h plus ion is released in alcohol all right you have read it in alcohol chapter roh here what you find it forms ro minus and h plus here also you can see that is h plus ion is released but is it alkoxide and stable due to resonance no alkoxide is not stability resonance due to which the equilibrium is favored in backward direction and hence h plus ion readily it's not readily released little bit of h plus sign is released and hence alcohol is less very slightly acidic in nature it is less acidic than water also what it gives study water is more acidic than alcohol so release of h plus sign does not means it is acidic at the same time this this particular product has to be stable because if this product is stable then only the equilibrium favor in forward direction so here in carboxylic acid that takes place this product is stable i've explained you hence equilibrium is favored in forward direction due to this reason it is a strong acid it behaves as a strong acid carboxylic acid all right so if you compare carboxylic acid and alcohol then here s plus n is readily released and hence this also is stable then compared to alkoxide ion and hence it is more stronger more acidic in nature so this all you understood about the nature of the structure of the acid thank you