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प्रश्न
Write the molecular formulae of the following compound.
Sodium aluminate
उत्तर
Sodium aluminate- NaAlO2
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संबंधित प्रश्न
Why do gold ornaments look new even after several years of use?
How is manganese extracted from manganese dioxide, MnO2? Explain with the help of an equation.
Which one of the methods given in column I is applied for the extraction of each of the metals given in column II:
| Column I | Column II |
| Electrolytic reduction | Aluminium |
| Reduction with Carbon | Zinc |
| Reduction with Aluminium | Sodium |
| Iron | |
| Manganese | |
| Tin |
Why does aluminium not corrode right through?
Which metal is extracted from calamine ore?
How is copper extracted from its sulphide ore (copper glance), Cu2S? Explain with equations of the reactions involved.
Zinc blende ore can be converted into zinc oxide by the process of:
(a) roasting
(b) hydrogenation
(c) chlorination
(d) calcination
When an object made of metal A is kept in air for a considerable time, it loses its shine and becomes almost black due to the formation of a layer of substance B. When an object made of another metal C is kept in damp air for a considerable time, it gets covered with a green layer of substance D. Metal A is the best conductor of electricity whereas metal C is the next best conductor of electricity.
(a) What is metal A?
(b) What is metal C?
(c) Name the substance B.
(d) Name the substance D.
Give the principles of the froth floatation process.
Give reasons, why aluminum is used in:
painting electric and telegraphic poles
What is meant by concentration of ores?
Heating an ore in a limited supply of air or in the absence of air at a temperature just below its melting point is known as ______.
Zinc sulphide : Roasting : : zinc carbonate : _______
Write the molecular formulae of the following compound.
Cryolite
Observe the figure and answer the following.
- Write the name of the method.
- What is used as anode and cathode in this method?
- Write the molecular formula and use of cryolite.
- Write anode reaction.
- Write cathode reaction.
Which of the following metals exist in their native state in nature?
(i) Cu
(ii) Au
(iii) Zn
(iv) Ag
The given reaction shows one of the processes to extract the metals like Iron and Manganese.
\[\ce{MnO2(s) + Al(s) -> Mn(l) + Al2O3(s) + Heat}\]
Identify the substance oxidised and reduced in the above reaction.
Assertion (A): The extraction of metals from their sulphide ores cannot take place without roasting the ore.
Reason (R): Roasting converts sulphide ores directly into metals.
