I was able to rule out A because adding more NH3 would shift it to the product side and therefore increase solubility but I have no idea how to approach it after that 😕
ETA: Yes, I forgot to say the answer is B
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Gen chem problem
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I was able to rule out A because adding more NH3 would shift it to the product side and therefore increase solubility but I have no idea how to approach it after that 😕
ETA: Yes, I forgot to say the answer is B
Yes. Ammonia is the ligand that forms a complex ion with silver. This will increase the solubility of silver chloride. YOu can also look the Ksp (in water) and the K for the reaction (aqueous ammonia) and see that AgCl is more soluble in aqueous ammonia
I didn't really solve any equation. The solubility product (just water) is on the order of 10^-10. They also provide the equilibrium constant for the formation of the complex ion, which is on the order of 10^-3. This was in aqueous ammonia. YOu can see that by adding ammonia, the products are more favorable at equilibrium. Anytime you can shift the equilibrium to the right, you are increasing hte solubility of the solid. This is happening because the complex ion formation removes "free" silver ions from solution.
Boom! Heres the answer from wikipedia and also in part from Chads videos.
"The solubility of a sparingly soluble salt (AgCl) is reduced in a solution that contains an ion in common with that salt. For instance, the solubility of silver chloride in water is reduced if a solution of sodium chloride is added to a suspension of silver chloride in water."
So, in that question, since AgCl reacts with NH3 that has no common ions with AgCl, the effect will be opposite, and AgCl will be more soluble than NH3
??? AgCl is not more soluble than ammonia in water. What you need to realize is that when ammonia forms a complex ion with silver ions, it is reducing the free concentration of silver ions in solution. This shifts the equilibrium to the right as more AgCl will ionize to replace the free silver ions. As a result, more of the solid breaks down, thus increasing the solubility of the solid. It is opposite to the common-ion effect you just cited.
alright thanks. So is AgCl more soluble in NH4 than because it forms a positively charged complex ion? I thought complex ions were soluble because of their positive charge.
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Think of it like this. AgCl normall would be as follows
AgCl ---> Ag+ (aq) + Cl- (aq)
If you add NH3 then the Ag+ on the right side would react with NH3 to form Ag(NH3)2+. This would shift the reaction to the right because the Ag+ is being used up therefore, the solubility of AgCl is increased as more is being dissociated.
AgCl ---> Ag+ (aq) + Cl- (aq)
If you add NH3 then the Ag+ on the right side would react with NH3 to form Ag(NH3)2+. This would shift the reaction to the right because the Ag+ is being used up therefore, the solubility of AgCl is increased as more is being dissociated.
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I was able to rule out A because adding more NH3 would shift it to the product side and therefore increase solubility but I have no idea how to approach it after that 😕
ETA: Yes, I forgot to say the answer is B
Answer A is wrong. Even if you don't know how NH3 would react with AgCl, you should still understand that if you add more solvent, then your solubility will increase, NOT decrease.
Answer C is wrong. Common ion effect is the reason.
Now it's between B or D. You need to know solubility rules of AgCl in water and ammonia. Normally any solvent containing metals in group one or 2 and Ammonia (NH3). have very good solubility.
I might be wrong but thats what I remember from my class
(taken 2 years ago).
