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प्रश्न
A student was asked to perform an experiment in the laboratory based on the instructions given:
Observe the picture given below and state one observation for the experiment you would notice on mixing the given solution.
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उत्तर
Blue precipitate dissolves to form an inky blue/deep blue solution.
Explanation:
The light blue precipitate of copper(II) hydroxide (Cu(OH)2) dissolves in excess of ammonium hydroxide due to the formation of a deep blue complex, tetraamminecopper(II) ([Cu(NH3)4]2+), making it soluble.
संबंधित प्रश्न
What do you observe when ammonium salt is heated with caustic soda solution?
Name a white, insoluble oxide that dissolves when fused with caustic soda or caustic potash.
Using sodium hydroxide solution, how will you distinguish: Zinc nitrate solution from calcium nitrate solution
Using sodium hydroxide solution, how will you distinguish:
Lead hydroxide from magnesium hydroxide.
Sodium hydroxide solution is added to solution A. A white precipitate is formed which is soluble in excess sodium hydroxide. Name the metal ion present in A.
Write the observation, and balanced equation for the following reaction:
Sodium hydroxide is added dropwise to a solution of zinc sulphate, till it is in excess.
Choose the correct answer from the options given below :
Hydroxide of this metal is soluble is sodium hydroxide solution
A white solid A when heated with sodium hydroxide solution, gives a pungent gas B, which turns red litmus blue. The solid, when dissolved in dilute nitric acid and treated with silver nitrate gives a white precipitate of C which is soluble in an ammonia solution.
Sodium hydroxide solution is added first in a small quantity, then in excess to the aqueous salt solutions of copper (II) sulphate, zinc nitrate, lead nitrate, calcium chloride, and iron (III) sulphate. Copy the following table and write the colour of the precipitate in (i) to (v) and the nature of the precipitate (soluble or insoluble) in (vi) to (x).
| Aqueous salt solution | Colour of precipitate when NaOH is added in a small quantity | Nature of precipitate (soluble or insoluble) when NaOH is added in excess |
| Copper (II) sulphate | (i) | (vi) |
| Zinc nitrate | (ii) | (vii) |
| Lead nitrate | (iii) | (viii) |
| Calcium chloride | (iv) | (ix) |
| Iron (III) Sulphate | (v) | (x) |
Distinguish by adding:
Sodium hydroxide solution and ammonium hydroxide solution to calcium salt solution and lead salt solution.
