Why do double displacement reaction occur?

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Double displacement reactions occur primarily due to the formation of more stable products from the interaction of ionic compounds in solution. In the case of AgNO3 and NaCl, both compounds dissociate into their respective ions in aqueous solution. The reaction leads to the formation of AgCl, which is insoluble and precipitates out of the solution, along with NaNO3, which remains dissolved. This process highlights the importance of ion exchange, as it allows for the formation of a solid product from previously stable ionic compounds. The driving force behind these reactions is the stability of the resulting compounds, particularly when one of the products is insoluble in the solvent, prompting the ions to bond more effectively and precipitate. The discussion emphasizes that the net ionic reaction reveals the underlying interactions and transformations occurring during the reaction, distinguishing it from other mixtures of ionic compounds that do not produce insoluble products.
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What's the reason for which double displacement reaction occur? Why there is a need for ion exchange between two compounds? They are already in a bonded state, a stabilised one. So what benefit would a double displacement reaction give?
The ionic reaction
AgNO3 +NaCl - - - - > AgCl(ppt) + NaNO3

(I think that due the reason that Eored for Ag is more than for Na the reaction must have occurred. But still it doesn't seem satisfying... Please explain. Thanks in advance.)
 
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Quotes said:
They are already in a bonded state, a stabilised one.

Doesn't mean they can't bond better, getting more stabilized.

But your example is trivially wrong - it is not AgNO3 that reacts with NaCl. Write the net ionic reaction and you will see what is really happening.
 
Borek said:
Doesn't mean they can't bond better, getting more stabilized.

But your example is trivially wrong - it is not AgNO3 that reacts with NaCl. Write the net ionic reaction and you will see what is really happening.
AgNO3 and NaCl dissociates into ions in aqueous solution and forms the products mentioned above which are more stable than the reacting compounds. Is this correct?
 
Quotes said:
AgNO3 and NaCl dissociates into ions in aqueous solution and forms the products mentioned above which are more stable than the reacting compounds. Is this correct?

It doesn't say anything about why - and how the situation described differs from - say - the mixture of NaCl and KNO3.
 
NaCl and AgNO3 are both ionic compounds capable of dissociation in water. So when aqueous solutions of both of these compounds are mixed you will have one contain of water which has Na+, Ag+, Cl-, and NO3- ions dissolved in it.

But wait, nothing is stopping these ions from interacting and colliding with one another in the aqueous environment. AgCl is not able to dissolve in water though, so when Ag+ and Cl- find each other, they stay that way as AgCl and crash out (precipitate).

The same dissociation happens when any two soluble ionic compounds are mixed. The difference is, do they for something that is insoluble in the environment they are in or not?
 
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