Advertisements
Advertisements
प्रश्न
You are given three white powders-calcium carbonate, lead carbonate and zinc carbonate. Describe the tests you would carry out in solution, to identify the metal ion in each of the above compounds. Indicate clearly how you would prepare the solutions for the tests.
Advertisements
उत्तर
The solutions for the tests will be prepared by dissolving the given powders separately in water.
(i) Solution of Calcium carbonate:
Calcium carbonate is CaCO3 and contains Ca2+ ions. Sodium hydroxide solution NaOH can be used to identify Ca2+ since its addition to calcium carbonate solution will give white precipitates of Ca(OH)2 which are sparingly soluble in excess of NaOH.
(ii) Solution of Lead carbonate:
Lead carbonate is PbCO3 and contains Pb2+ ions. Ammonium hydroxide solution NH4OH can be used to identify Pb2+ since its addition to lead carbonate solution will give white precipitates of Pb(OH)2 which are insoluble in excess of NH4OH.
(iii) Solution of Zinc carbonate:
Zinc carbonate is ZnCO3 and contains Zn2+ ions. Sodium hydroxide solution NaOH can be used to identify Zn2+ since its addition to zinc carbonate solution will give white gelatinous precipitates of Zn(OH)2 which are soluble in excess of NaOH.
APPEARS IN
संबंधित प्रश्न
Identify the salts P and Q from the observations given below:
On performing the flame test salt P produces a lilac coloured flame and its solution gives a white precipitate with silver nitrate solution, which is soluble in Ammonium hydroxide solution.
Name a solution that will separate the component of the following mixture: Zn(OH)2 from Pb(OH)2
Choose the correct answer from the options given below :
Which one is colourless anion?
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 precipiatate (soluble or insoluble) in (vi) to (x)
| Aqueous salt Solution | Colour of Participitate when NaOH is added in a samll quantity | Nature of precipitate(soluble or insoluble) when NaOH added in excess |
| Copper (II) Solution | ||
| Zinc nitrate | ||
| Lead nitrate | ||
| Calcium chloride | ||
| Iron(III) sulphate |
Give one chemical test to distinguish between the following pair of compounds:
Zinc sulphate solution and Zinc chloride solution
Give the balanced equations for the reaction with two different amphoteric oxides with a caustic alkali.
A given white crystalline salt was tested as follows:
The addition of barium chloride solution into this solution gave a white precipitate. What conclusions can be drawn for the observation?
When an ammonium hydroxide solution is added to solution B, a pale blue precipitate is formed. This pale blue precipitate dissolves in excess ammonium hydroxide giving an inky blue solution. What is the cation present in solution B?
When an ammonium salt is warmed with sodium hydroxide solution, a gas is evolved. State three ways in which you could identify this gas.
Write balanced equation for a metal that evolves a gas which burns with a pop sound when boiled with alkali solutions.
