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Nitro group (-NO2), having -I and -R effect, is an electron withdrawing and deactivating group. Due to both these effects, it decreases electron density around the -COOH group of substituted(ortho, meta & para) benzoic acids and releases H+ ions, making these acidic. The nitrobenzoic acid which releases H+ group more easily is the most acidic.
Due to ortho effect, ortho acids are more acidic than all other substituted acids(even if an electron donating group is present at the ortho position. The only exception is -NH2 group, in which ortho- aminobenzoic acid is NOT the strongest acid).
Regarding acidity of meta and para acids, consider I and R effects. Inductive effects of meta and para acids reduce electron density around -COOH group, whereas resonance does not occur at meta position. It only occurs at para position, making the nitro group at para position a more strong withdrawer of electrons. Thus para-nitro benzoic acid is more acidic than meta-nitro benzoic acid.
In short, the higher acidity of p-nitrobenzoic acid compared to m-nitrobenzoic acid is attributed to its -I and -R effect.
Wiki User
∙ 11y ago
Wiki User
∙ 14y agoThis may be due to the resonance effect of the chlorine atom. Resonance effect is the ability of the substituting group on the benzene ring to withdraw or donate an electron. Chlorine has high electronegativity, so it has electron withdrawing properties. In meta position it is closer to the acid group and can pull the electron away from the hydrogen atom stronger than in para position. By doing that, the chlorine atom stabilizes the electron making it easier for the proton to leave. As a result, the hydrogen atom becomes more acidic.
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Uses of ortho iodo benzoic acid?
Yeah, so of ortho simply iodo benzoic acid.
What is the picricacid formual?
picric acid (or 2,4,6-trinitrophenol) is more acidic than benzoic acid The pKa or picric acid is 0.3 and that of benzoic acid is 4.2
Why 4 hydroxy benzoic acid is less acidic than 2 hydroxy benzoic acid?
as because in 2-hydroxy benzoic acid, there is a possibility of H-bonding which makes the dissociated ion stable and will not combine with H+ ion leaving it free, while it is not so in case of 4-hydroxy benzoic acid.
Is Benzoic acid intensive or extensive?
Neither. Benzoic acid is... benzoic acid. Intensive and extensive are properties are characteristics of elements and compounds such as color, density, odor, conductivity, etc. To say benzoic acid is extensive or benzoic acid is intensive doesn't make sense.
Chemical name of salicyclic acid?
O-hydroxy benzoic acid or 2-hydroxy benzoic acid.
Which is more acidic ortho-nitro benzoic acid or ortho-methoxy benzoic acid?
orho methoxy benzoic acid is more acidic due to stability achieved due to chelation effect.
Uses of ortho iodo benzoic acid?
Yeah, so of ortho simply iodo benzoic acid.
Which is more acidic formic acid or benzoic acid?
Benzoic Acid
Why ortho chlorobenzoic acid is stronger than benzoic acid?
conjugatory effect
Is benzamide acidic?
No; the derivate benzoic acid is of course acidic.
Why o-hydroxy benzoic acid is strong than m-hydroxy benzoic acid?
nswers for Orthohydroxybenzoic Acid Is More Acidic Then The Parahydroxy Benzoic Acid
Why is methanoic acid more acidic than benzoic acid?
We would certainly expect benzoic acid to be more acidic than methanoic acid, due to stabilisation of the benzoate anion caused by the delocalisation of the electrons on the oxygen atom over the benzene ring. However, in practice, it is found that methanoic acid is actually more acidic than benzoic acid(has a greater Ka value). This is because methanoic acid is more soluble in water than benzoic acid, so there is greater ionisation of methanoic acid in water than benzoic acid.
What has the author Marion Byrd Hopkins written?
Marion Byrd Hopkins has written: 'The chlorides of ortho-sulpho-benzoic acid ..' -- subject(s): Chlorides, Sulphobenzoic acid, Ortho-
What is the picricacid formual?
picric acid (or 2,4,6-trinitrophenol) is more acidic than benzoic acid The pKa or picric acid is 0.3 and that of benzoic acid is 4.2
Why toluene does not react with acidic or alkaline permanganates?
Toluene reacts with acidic permanganate on heating and forms the Benzoic acid.
Why 4 hydroxy benzoic acid is less acidic than 2 hydroxy benzoic acid?
as because in 2-hydroxy benzoic acid, there is a possibility of H-bonding which makes the dissociated ion stable and will not combine with H+ ion leaving it free, while it is not so in case of 4-hydroxy benzoic acid.
Which is more acidic benzoic acid or acetic acid?
Benzoic acid is the stronger acid compared to ethanoic acid. However, ethanoic acid is more corrosive and will burn skin etc more than benzoic acid. Corrosivity/burn potential are not the same as acid strength. This is due to the delocalisation of the lone pair of electrons on the oxygen atom into the benzene, increasing the polarity of the -OH bond and thus makes the cleaving of the H+ ion easier. The delocalisation of electrons into the benzene ring also stabilises the carboxylate ion. Therefore the position of equilibrium lies more to the right and this shows that benzoic is a more acidic acid. The simplified version is that a benzene ring is electron withdrawing and a methyl group is electron releasing. The electron withdrawing power makes the releasing of the H+ ion easier.
