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प्रश्न
Aluminium oxide is _______ oxide.
पर्याय
acidic
basic
neutral
amphoteric
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उत्तर
Aluminium oxide is amphoteric oxide.
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संबंधित प्रश्न
Give reasons.
Carbonate and sulphide ores are usually converted into oxides during the process of extraction.
A man went door to door posing as a goldsmith. He promised to bring back the glitter of old and dull gold ornaments. An unsuspecting lady gave a set of gold bangles to him which he dipped in a particular solution. The bangles sparkled like new but their weight was reduced drastically. The lady was upset, but after a futile argument, the man beat a hasty retreat. Can you play the detective to find out the nature of the solution he had used?
M is a metal above hydrogen in the activity series and its oxide has the formula M2O. This oxide when dissolved in water forms the corresponding hydroxide which is a good conductor of electricity. In the above context, answer the following:
1) What kind of combination exists between M and O?
2)How many electrons are there in the outermost shell of M?
3) Name the group to which M belongs.
4) State the reaction taking place at the cathode.
5) Name the product at the anode.
How many carats is pure gold? Why is pure gold not suitable for making ornaments?
How is manganese extracted from manganese dioxide, MnO2? Explain with the help of an equation.
What is meant by the 'concentration of ore'?
Name the chemical compound which is electrolysed in molten state to obtain sodium metal. Which gas is produced in this process?
How is aluminium metal extracted? Explain with the help of an equation.
In an electrolytic tank, aluminium metal is being extracted by the electrolysis of molten aluminium oxide using carbon electrodes. It is observed that one of the carbon electrodes is gradually burnt away and has to be replaced.
(a) Which carbon electrode (cathode or anode) is burnt away?
(b) Why is this carbon electrode burnt away?
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.
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Give reasons, why aluminum is used in:
wrapping chocolates
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painting electric and telegraphic poles
Name the ore of mercury. With the help of balanced chemical equations, explain the process of extraction of mercury from its ore.
In Electrolytic reduction of alumina, Anode : _______ : : Cathode : Graphite lining
Zinc sulphide : Roasting : : zinc carbonate : _______
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Explain in brief types of extraction of less reactive metals according to their reactivity.
The process in which a carbonate ore is heated strongly in the absence of air to convert it into metal oxide is called ____________.
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.
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.
