Akhil jain
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Practical chemistry and common ion effect
Mant times I have tried this experiment but every time I get a precipitate. I take some zinc chloride soln. in a test tube ,add NH4Cl in it and then
add NH4OH but always i get a ppt and according to this book Zinc ions should not ppt due to common ion effect and their higher solubility product .
Same thing is happening with manganese instead of precipitating in group 4 they get ppt in group 3 .
Guys please try this and tell is same happening with you
These are photos of that book . You may understand from this what I want to say
 
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Metacelsus
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Zinc hydroxide is insoluble, but in excess ammonia it dissolves to form an ammine complex. If you want it to dissolve, try adding more ammonia.
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Akhil jain
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I know that it dissolves in excess ammonia but what about the analysis .you aren't getting my point . What about common ion effect
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Akhil jain
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Plz try the experiment and tell me did the same happened with you
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DraconicAcid
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You need to add more ammonium chloride if you want to see the common ion effect in action.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Akhil jain
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Have you tried
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Akhil jain
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Ya bro you were right . I tried and this time I could not get a ppt with zinc ions but got a ppt with Fe2+ ions. Why did they get precipitated their
solubility product is almost of same order of other ions of group 4
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DraconicAcid
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Because zinc forms a complex ion with ammonia, and iron doesn't.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Akhil jain
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Then what about common ion effect
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