Advertisements
Advertisements
Question
Explain the following method with example.
Direct combination
Advertisements
Solution
Direct combination i.e. by heating two elements together
\[\ce{Metal + Non metal -> Salt}\]
\[\ce{2Na(molten) + Cl2 -> 2NaCl}\]
\[\ce{2Fe + 3Cl2 -> 2FeCl3}\]
APPEARS IN
RELATED QUESTIONS
How is the following salt prepared:
Copper (II) sulphate from copper (II) oxide?
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.
Explain why fused calcium chloride is used in the preparation of FeCI3?
Some methods used for the laboratory preparation of salts are:
(a) Metal + acid
(b) Carbonate + acid
(c) Precipitation
(d) Direct combination
(e) Titration
Copy and complete the following table :
| Salt | Method of Preparation |
| Ammonium Sulphate | |
| Calcium carbonate | |
| Iron (III) chloride | |
| Lead nitrate | |
| Zinc sulphate |
Write the balanced equation for the preparation of the following compounds, starting from iron and other substance:
Iron (II) sulphide
The preparation of lead sulphate from lead carbonate is a two step process (lead sulphate cannot be prepared by adding dilute sulphuric acid to lead carbonate)
What is the first step that is required to prepare lead sulphate from lead carbonate?
Give the equation for the preparation of the following salt from the starting material given.
Iron (III) Chloride from Iron
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 |
For the preparation of the following salts - give a balanced equation in the following case.
Lead [II] chloride from lead carbonate [give two equations]
