Advertisements
Advertisements
प्रश्न
You are provided with PbCO3, ZnCO3 and CaCO3. How will you identify these cations?
Advertisements
उत्तर
By use of Ammonium hydroxide we can identify the ions PbCO3, ZnCO3 and CaCO3 as :
(i) \[\ce{PbCO3 + 2NH4OH -> Pb(OH)2 v + 2NH4NO3}\]
Pb(OH)2 forms white precipitate which are insoluble in excess ammonium hydroxide.
(ii) \[\ce{ZnCO3 + NH4OH -> Zn(OH)2 v + 2Na2CO3}\]
Zn(OH)2 forms white gelatinous precipitate which are soluble in excess ammonium hydroxide.
(iii) \[\ce{CaCO3 + NH4OH -> Ca(OH)2 + 2Na2CO3}\]
No precipitation of Ca(OH)2 occurs even with addition of excess of NH4OH. Because the concentration of hydroxide ion from ammonium hydroxide is so low that it cannot precipitate the hydroxide of calcium.
Concept Insight : Some precipitated metallic hydroxides by ammonium hydroxide become soluble hydroxides when treated with excess of ammonium hydroxide due to the formation of a soluble complex salt in the presence of excess of ammonium hydroxide.
APPEARS IN
संबंधित प्रश्न
How will you distinguish between Ammonium hydroxide and Sodium hydroxide using copper sulphate solution?
What happens when ammonia solution is added first dropwise and then in excess to the following solution:
ZnSO4
Write a balanced equation for this reaction.
Write the observation, and balanced equation for the following reaction:
Ammonium hydroxide is added first in a small quantity, and then in excess, to a solution of copper sulphate.
What would you observe in the following cases:
Ammonium hydroxide is first added in a small quantity and then in excess to a solution of copper sulphate.
Identify the cation of the following case:
NaOH solution when added to solution (A) gives a reddish brown precipitate
Write balanced equation:
Copper sulphate solution with ammonium hydroxide solution.
Write a balanced equation:
Copper sulphate solution with ammonium hydroxide solution.
Write balanced equation:
Copper sulphate solution with ammonium hydroxide solution.
Write balanced equation:
Copper sulphate solution with ammonium hydroxide solution.
Write balanced equation:
Copper sulphate solution with ammonium hydroxide solution.
