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प्रश्न
How do the properties of an alloy differ from alloy constituents?
उत्तर
- The properties of alloys are often greatly different from those of the components.
- For example, gold is too soft to be used without a small percentage of copper.
- A low percentage of molybdenum improves the toughness and wear resistance of steel.
- Bell metal is more sonorous than copper or tin.
- Alnico, an alloy of aluminium, nickel, and cobalt, can lift 60 times its mass.
- These added elements improve hardness, wear resistance, toughness and other properties.
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संबंधित प्रश्न
Name the process by which impure ore of aluminium gets purified by using the concentrated solution of an alkali.
How does aluminum react with the Water ?
Name an ore which is concentrated by:
forth floatation process
Give three ways in which the metal zinc differs from the non-metals carbon. At least one of the differences must be a chemical difference?
From the metals: copper iron, magnesium, sodium and zinc, select a different metal in each case
which:
for not react with cold water but reacts with steam when heated.
Name the following:
Two metals which occur in nature in free state as well as in combined state.
| 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.
Name the following :
An ore of zinc containing its sulphide.
In the Wilfley table method, the particles of gangue are separated by __________ separation method.
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?
