Nucleophilic Substitution Reaction: CH3Cl + AgF

[Karan Punjabi]

CH3Cl +AgF :CH3F +AgCl
Guys if I'm correct this is a nucleophilic substitution reaction and here I'm not getting the reaction because from my view chlorine atom is more nucleophilic than fluorine atom and carbon atom is more electronegative than silver atom so how the reaction is taking place?

 

[Borek]

What do you know about the stability of AgCl?

 

[Karan Punjabi]

What do you know about the stability of AgCl?

I think thaf AgF is more stable than AgCl and I'm studying in FYJC science. So please can you provide answers according to my level of education

 

[Borek]

Which is more soluble?

 

[Karan Punjabi]

Which is more soluble?

If in water i think so AgF

 

[Karan Punjabi]

If in water i think so AgF

But from this how i will understand the reaction?

 

[Borek]

AgCl is much more stable than AgF - this is reflected by their solubilities in water. Thus conversion of AgF to AgCl is a driving force for many reactions.

 

[Karan Punjabi]

AgCl is much more stable than AgF - this is reflected by their solubilities in water. Thus conversion of AgF to AgCl is a driving force for many reactions.

Can you explain it a little better...I'm not getting that. If swarts reaction is happening than the electronegativity and nucleophilicness of atoms in this reaction are not working.

 

[Borek]

They do, but the fact that AgCl is much stable counteracts it. AgCl stability means you are effectively removing chlorine from the reaction mixture.

 

[Karan Punjabi]

They do, but the fact that AgCl is much stable counteracts it. AgCl stability means you are effectively removing chlorine from the reaction mixture.

Ok i understood, then there would be many reactions like this case. Correct? Can you also tell me on what basis is the AgCl more stable than AgF

 

[DrDu]

As Borek said, AgCl has a very low solubility in water in contrast to AgF which is completely soluble (under the conditions of the reaction).
Solubility is not mainly a question of stability of the salt, but also of the energetic stabilization of the ions in the solution. Fluorine anions are much smaller than Cl- anions and can also form hydrogen bonds, which increases solution enthalpy of AgF. Hence AgF is very soluble in contrast to AgCl.
The nucleophilic substitution is an equilibrium reaction. With comparable amounts of Cl- and F- present, it may well be that the equilibrium is on the side of CH3Cl. But the formation of AgCl removes almost all Cl- anions from the solution as soon as they are formed whence the reaction will be pulled on the side of CH3F.