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प्रश्न
Distinguish between the given pair of compounds using the test given within bracket:
A lead salt and a zinc salt (using excess ammonium hydroxide)
Distinguish between the following pair of compounds using the test given within bracket.
A lead salt and a zinc salt (using excess ammonium hydroxide)
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उत्तर
| Lead salt | Zinc salt | |
| 1. | On adding ammonium hydroxide, a white precipitate of lead hydroxide, Pb(OH)2, is formed. | On adding ammonium hydroxide, a white gelatinous precipitate of zinc hydroxide, Zn(OH)2, is formed. |
| 2. | The precipitate does not dissolve in excess ammonium hydroxide. | The precipitate dissolves in excess ammonium hydroxide, forming a clear solution. |
Hence, lead salt remains insoluble, while zinc salt dissolves in excess ammonium hydroxide.
संबंधित प्रश्न
How is the following salt prepared:
Calcium sulphate from calcium carbonate,
Give the preparation of the salt shown in the left column by matching with the methods given in the right column. Write a balanced equation for each preparation.
| Salt | Method of preparation |
| Zinc Sulphate | Precipitation |
| Ferrous sulphide | Oxidation |
| Barium Sulphate | Displacement |
| Ferric sulphate | Neutralisation |
| Sodium sulphate | Synthesis |
Explain why It is necessary to find out the ration of reactants required in the preparation of sodium sulphate.
State how would you prepare copper (II) oxide from
Copper Carbonate
Write the balanced equation for the preparation of the following compounds, starting from iron and other substance:
Iron (II) sulphate
Write the equation for the laboratory preparation of sodium sulphate using dilute sulphuric acid.
Fill in the blanks with suitable words:
An acid is a compound which when dissolved in water forms hydronium ions as the only ______ ions. A base is a compound which is soluble in water and contains ______ ions. A base reacts with an acid to form a ______ and water only. This type of reaction is known as ______.
Mention the colour changes observed when the following indicators are added:
| Solution | Acids | Alkalies |
| (a) Alkaline phenolphthalein solution | ||
| (b) Methyl orange solution | ||
| (c) Neutral litmus solution |
The following is a list of methods for the preparation of salts.
A – direct combination of two elements.
B – reaction of a dilute acid with a metal.
C – reaction of a dilute acid with an insoluble base.
D – titration of a dilute acid with a solution of soluble base.
E – reaction of two solutions of salts to form a precipitate.
Choose from the above list A to E, the best method of preparing the following salt by giving a suitable equation in the following case:
Copper sulphate.
Select the word/s given which are required to correctly complete the blanks.
When solution M and O are mixed together, the products will be ______ and ______.
