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प्रश्न
Give reason for the following:
Nitric acid can be stored in aluminium containers.
उत्तर
Nitric acid can be stored in aluminium containers because it do not attack aluminium. It renders aluminium passive due to the formation of an oxide film on surface of aluminum.
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संबंधित प्रश्न
Name the following: A compound added to lower the fusion temperature of electrolytic bath in the extraction of aluminum
Aluminium is a more active metal than iron, but suffers less corrosion. Why?
Explain with reason:
Carbon can reduce lead oxide but not aluminium oxide.
In order to obtain one tone of aluminium, the following inputs are required:
4 tones of bauxite, 150 Kg of sodium hydroxide and 600 Kg of graphite.
The aluminium compound in bauxite is aluminium oxide and the main impurity is iron (II) oxide. Aluminium is obtained by the electrolysis of aluminium oxide dissolved in cryolite.
In construction work, why is the alloy of aluminium, duralumin used rather than pure aluminium.
The following is an extract from 'Metals in the Service of Man, Alexander and Street/Pelican 1976':
| 'Alumina (aluminium oxide) has a very high melting point of over 2000°C so that it cannot readily be liquefied. However, conversion of alumina to aluminium and oxygen, by electrolysis, can occur when it is dissolved in some other substance.' |
- Which solution is used to react with bauxite as a first step in obtaining pure aluminium oxide?
- The aluminium oxide for the electrolytic extraction of aluminium is obtained by heating aluminium hydroxide. Write the balanced chemical equation for this reaction.
- Name the element which serves both as the anode and the cathode in the extraction of aluminium.
- Write the balanced chemical equation for the reaction that occurs at the cathode during the extraction of aluminium by electrolysis.
- Give the balanced chemical equation for the reaction which occurs at the anode when aluminium is purified by electrolysis.
Describe the role played in the extraction of aluminum:
Cryolite
Explain why it is preferably to use a number of graphite electrodes as anode instead of a single electrode, during the above electrolysis.
Name the following:
A metal which is always present in the amalgam.
What impurities are present in aluminium ore?
State true or false.
Bauxite is the main ore of aluminium.
