@ tarin

thanx for showing my mistake



ya

m-nitro benzoic acid is stronger acid



as NO2 attracts the electron towards itself, it creates attracts the e from C to which it is attached..................................which indeed attracts the e from other carbon atom and in this way, -COOH becomes a better H repelling group

the same thing happens with fluoro group also



but now another criterion comes into picture

that is the distance

NO2 is more closer to COOH then F

so its -I effect is more

also NO2 is better e attracting group as compared to F



so considering both the facts, m-nitro benzoic acid is a stronger acid

so here the two cases important in deciding the acid strngth are

1. distance from COOH


2. relative -I effect of NO2 and F