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प्रश्न
What is the role of flux in metallurgical processes?
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उत्तर
The ores, even after concentration, contain some gangue. To remove gangue, certain substances are mixed with concentrated ore which combine with the gangue to form a fusible material which is not soluble in molten metal. The substances used are called fluxes.
Fluxes are classified as:
(i) Acidic flux and
(ii) Basic flux. Acidic flux removes basic impurities while basic flux removes acidic impurities.
APPEARS IN
संबंधित प्रश्न
State the main components of the following alloys:
Brass
Which process is applied to concentrate ore of zinc?
Which impurities are present in bauxite?
How does aluminum react with the Acid ?
State on what special properties the use of each of these metals depends:
aluminium
Explain the following term:
Ores
Name the following :
Ore of iron referred to as "fool's gold".
Define the term : Ore
What is an amalgam? Name one metal which does not form amalgam? State one use of amalgam.
Give composition and uses of the following alloys. Mention the reason for its use.
Brass
Explain the following:
Aluminium is extensively used for making aircraft parts.
Give the name and formula of an ore of zinc.
Reduction of the zinc compound which is the product of above reaction.
Give the name and formula of an ore of zinc.
What in addition to a zinc compound, is put into the furnace? State one large scale use of zinc.
| X | Y | |
| Normal Electronic Configuration | 2, 8, 7 | 2, 8, 2 |
| Nature of Oxide | Dissolves in water and truns blue litmus red. | Very low solubility in water. Dissolves in hydrochloric acid. |
| Tendency for Oxidising and reducing reactions | Tends to oxidise elements and compound. | Tends to act as a reducing agent. |
| Electrical and Thermal Conductivity | Very poor electrical conductor. Poor thermal conductivity. |
Good electrical conductor. Good thermal conductor. |
| Tendency to form Alloys and Amalgams | No tendency to form alloys. | Forms alloys. |
Using the information above, complete the following:
- _________ is the metallic element.
- Metal atoms tend to have a maximum of ________ electrons in the outermost energy level.
- Non-metallic elements tend to form _________ oxides while metals tend to form _______ oxides.
- Non-metallic elements tend to be ______ conductors of heat and electricity.
- Metals tend to _______ electrons and act as ________ agents in their reactions with elements and compounds.
State the main components of the following alloy:
Brass
Name the following.
The property possessed by metals by which they can be beaten into sheets.
This is not an alloy of copper:
Draw diagram of magnetic separation process and answer the questions based on it.
- Give example in which this process can work.
- Suggest any two methods that can also be used for this purpose.
- Which technique is based on hydrophobic and hydrophilic properties of particles?
