Advertisements
Advertisements
प्रश्न
On adding dilute ammonia solution to a colourless solution of a salt, a white gelatinous precipitate appears. This precipitate, however, dissolves on addition of excess of ammonia solution. Identify (Choose from Na, Al, Zn, Pb, Fe).
- Which metal salt solution was used?
- What is the formula of the white gelatinous precipitate obtained?
On addition of dilute ammonia solution to a colourless salt solution, a white gelatinous precipitate is formed which dissolves when ammonia solution is in excess. Identify the metal from Na, Al, Pb, Fe, Zn whose salt solution is used. What is the formula of the precipitate formed?
Advertisements
उत्तर
(a) Zinc (Zn) metal salt solution was used.
(b) The formula of the white gelatinous precipitate is Zn(OH)2.
Concept Insight:
\[\ce{\underset{Colourless}{ZnSO4} + 2NH4OH ->\underset{White ppt.}{Zn(OH)2} + (NH4)2SO4}\]
With an excess of NH4OH the precipitate of zinc(II) hydroxide dissolves as:
\[\ce{Zn(OH)2 +\underset{In excess}{(NH4)2SO4 + 2NH4OH} ->\underset{\underset{(Colourless solution)}{Tetrammine zinc(II)Sulphate}}{[Zn(NH3)4]SO4}+ 4H2O}\]
संबंधित प्रश्न
Write the probable colour of the following salt:
Ammonium salts
Write the probable colour of the following salt:
Ferrous sulphate
Name the probable cation present in each of the following solution:
Light blue coloured solution
Name the probable cation present in each of the following solution:
Pink coloured solution
Write the colour of the following salts: Cuprous salts.
One chemical test that would enable you to distinguish between the following pair of chemicals. Describe what happens with each chemical or state 'no visible reaction'.
Sodium sulphate solution and sodium chloride solution.
Write balanced equation for the following reaction:
Iron(II) chloride solution with sodium hydroxide solution.
Write balanced equation for the following reaction:
Zinc and sodium hydroxide solution
Colour of an aqueous solution of copper sulphate is ______.
Colour of the precipitate formed on adding NaOH solution to iron (II) sulphate solution is ______.
