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प्रश्न
Write the name.
The molecular formula of main ore of aluminium -
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उत्तर
Al2O3 · nH2O
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संबंधित प्रश्न
Metallic oxides of zinc, magnesium and copper were heated with the following metals.
| Metal | Zinc | Magnesium | Copper |
| Zinc oxide | – | – | – |
| Magnesium oxide | – | – | – |
| Copper oxide | – | – | – |
In which cases will you find displacement reactions taking place?
Which metal becomes black in the presence of hydrogen sulphide gas in air?
The non-metal present in steel is ______.
How are the less reactive metals (which are quite low in the reactivity series) extracted? Explain with the help of an example.
How is aluminium metal extracted? Explain with the help of an equation.
Name the electrode at which aluminium metal is produced.
Name one ore of mercury. Which mercury compound is present in this ore? Write its chemical formula.
An ore of manganese metal is ______.
The metal which can be extracted simply by heating the cinnabar ore in air is ______.
Give the principles of electromagnetic separation.
Write equations for each of the above metal which reacts with water.
Complete the incomplete statement with missing word:
Metals form positive ions while non- metals ______.
choose the most appropriate term to match the given description.
Heating of the ore in the absence of air to high temperature
Zinc sulphide : Roasting : : zinc carbonate : _______
Explain the characteristics of ionic compounds.
Explain Bayer’s process of concentration of bauxite with a chemical equation.
In thermite welding a mixture of ____________ is ignited with a burning magnesium ribbon which produces molten iron metal as a large amount of heat is evolved.
Iqbal treated a lustrous, divalent element M with sodium hydroxide. He observed the formation of bubbles in reaction mixture. He made the same observations when this element was treated with hydrochloric acid. Suggest how can he identify the produced gas. Write chemical equations for both the reactions.
On the basis of reactivity metals are grouped into three categories:
- Metals of low reactivity
- Metals of medium reactivity
- Metals of high reactivity
Therefore metals are extracted in pure form from their ores on the basis of their chemical properties.
Metals of high reactivity are extracted from their ores by electrolysis of the molten ore.
Metals of low reactivity are extracted from their sulphide ores, which are converted into their oxides. The oxides of these metals are reduced to metals by simple heating.
(a) Name the process of reduction used for a metal that gives vigorous reaction with air and water both.
(b) Carbon cannot be used as a reducing agent to obtain aluminium from its oxide? Why?
(c) Describe briefly the method to obtain mercury from cinnabar. Write the chemical equation for the reactions involved in the process.
OR
(c) Differentiate between roasting and calcination giving chemical equation for each.
