Welcome to Chem Zipper.com......: PHENOL

Search This Blog

Showing posts with label PHENOL. Show all posts
Showing posts with label PHENOL. Show all posts

Tuesday, June 9, 2020

Which is more acidic amongst phenol and phenoxide and why?

Why is acetic acid stronger than phenol?

Acetic acid furnished acetate ion by removal of  H+ which is more resonance stablised because in resonating structure of acetate ion, negative charge equilly distributed on both oxygen atom ,
While in phenoxide ion oxygen atom required partial positve charge which relatively destabilize.

Phenols are more acidic than alcohol.Why?

Alcohols and phenols both are acidic in nature because they Liberate H2 with active metals. But alcohols are weaker acids than phenols because,  
(i) Alcohols fail to turn blue litmus red:
(ii) Alcohols fail to neutralize alkalies whereas phenols do so:
(1) Both phenol and phenoxide ions exhibit resonance, whereas alcohols and alkoxide ion do not.
(2) Due to resonance, positive charge 's developed over "O" of phenol this weakens O-H bond and facilitates release of a proton. On the other hand due to electron donating nature of alkyl group -O-H bond is strengthened. Therefore it hinders the release of proton.      
(3) The phenoxide ion is more stable than phenol, due to greater dispersal of negative charge, therefore. Equilibrium get shifted to forward direction. whereas alkoxide ion is less stable than alcohols due to intensification of negative charge, so equilibrium get shifted towards backward direction. Hence phenols are more acidic than alcohols. 

Phenoxide ion is more stable than an alkaoxide. why?



Phenoxide ion is more stable than alkaoxide because phenoxide ion stabilised by resonance  whereas alkaoxide ion does not resonance stabilised .

Why O-nitrophenol is more volatile than p-nitrophenol ?

 O-nitrophenol is more volatile than p-nitrophenol because it has Intramolecular H-bond while p-nitrophenol has Intermolecular H-bond.