Which is more acidic p-fluorobenzoic acid or p-chlorobenzoic acid?

Fluorine is more electronegative than chlorine but p-fluorobenzoic acid is a weaker acid than p-chlorobenzoic acid. Both fluorine and chlorine are involved in -I effect as well as +M effect (due to presence of lone electron paris) with the benzene ring.

Why is p-fluorobenzoic acid less acidic than p-chlorobenzoic acid?

Fluorine is more electronegative than chlorine even then p-fluorobenzoic acid is a weaker acid than p-chlorobenzoic acid. Explain. -effect which outweighs the +R-effect. Consequently, p-fluorobenzoic acid is a weaker acid than p-chlorobenzoic acid.

Which is more acidic fluorobenzene or chlorobenzene?

Therefore, with longer C-Cl bond providing more polarity, but less inductive pull and less resonance push, chlorobenzene is likely to be more polar than fluorobenzene and therefore Ph-Cl has slightly higher DM than Ph-F.

Why is fluorine more acidic than chlorine?

Because the inductive effect depends on electronegativity, fluorine substituents have a more pronounced pKa-lowered effect than chlorine substituents.

Which is more acidic fluoroacetic acid or chloroacetic acid?

Answer: Electron withdrawing atoms or groups at alpha carbon atom increases stability of the carboxylate anion by dispersing the charge. Hence acidic nature also increases. Thus fluoro acetic acid is more acidic than chloro acetic acid.

Why is Fluorobenzene more reactive?

It is more reactive than a regular benzene ring because the methyl group is electron-donating, making the ring have greater electron density. Electron-donating groups have a positive inductive effect and make the main group more reactive. Electron-withdrawing groups do the opposite.

Is Fluorobenzene more reactive than benzene?

Depending on the electrophile, fluorobenzene has approximately the same rate of reaction as benzene in S E Ar (from 0.4-1.73 compared to rate = 1 for benzene) (Ault, 1966;Ault, 2004). …

Why is para-chlorobenzoic acid more acidic than para-fluorobenzosic acid?

First, it is true that para-chlorobenzoic acid is more acidic (pKa=3.98) than para-fluorobenzoic acid (pKa=4.14). Based on inductive effects (aka I-effect), fluorobenzoic acid should be more acidic as ‘F’ is more electronegative than ‘Cl’. The other consideration is resonance.

Why does the substitution of -OCH3 on benzoic acid decrease its acidic strength?

Substitution of −OCH3​on benzoic acid decreases its acidic strength because it is an activating group having +Meffect which increases electron density and destabilizes benzoate carbanion. The −NO2​group has −Meffect which withdraws electron density and forms stable benzoate carbanion and makes it a strong acid.

What is the Order of acidic strength of -NO2 group?

The −NO2​group has −Meffect which withdraws electron density and forms stable benzoate carbanion and makes it a strong acid. Therefore, the order of acidic strength is p−nitrobenzoicacid>benzoicacid>p−methoxybenzoicacid.