في تصنيف الكيمياء العضوية بواسطة

تبعاً للصورة المرفقة رتب المركبات حسب قوة الحامضية؟


1 إجابة واحدة

0 تصويتات
بواسطة

- الترتيب يكون كما بالشكل :

 a- O-hydroxy benzoic acid is the strongest acid here 

The OH in salicylic acid (the ortho-derivative) will stabilize the anion due to hydrogen bonding

 

(Hydrogen bonding is also possible in the protonated form (the acid) but is stronger in the carboxylate anion

b- m-hydroxy benzoic acid is more acidic than p-hydroxy benzoic acid 

 OH group at para position has dominant -M effect (mesomeric effect) but has -I effect  (inductive effect) also while OH group at meta position on benzene ring has only -I effect

When both acids donate their proton from -COOH group then p-hydroxybenzoate is more stabilized due to -M effect of nitro group than m-hydroxybenzoate because -M group more deactivates the ring / decreases charge than -I group

Thus, p-hydroxybenzoic acid is more acidic than m-hydroxybenzoic acid



اسئلة متعلقة



التصنيفات



...