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प्रश्न
Define roasting.
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उत्तर
Roasting is the process of heating concentrated ore to a high temperature in the presence of air. The process is usually carried out for sulphide ores.
संबंधित प्रश्न
Name the following:
Main ore of aluminium.
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.
In the extraction of aluminium: Draw the diagram for the extraction of aluminium.
Name one metal which is extracted by:
Reduction with heat alone.
Define the term gangue.
What is the difference between a mineral and an ore?
Explain how, mercury is extracted from its sulphide ore (cinnabar). Give equations of the reactions involved.
Which of the following is an ore of mercury metal?
Calamine ore can be used to extract one of the following metals. This metal is:
Which of the following reactants are used to carry out the thermite reaction required for welding the broken railway tracks?
Which of the following metals can be obtained from haematite ore?
A black metal oxide XO2 is used as a catalyst in the preparation of oxygen gas from potassium chlorate. The oxide XO2 is also used in ordinary dry cells. The metal oxide XO2 cannot be reduced satisfactorily with carbon to form metal X.
- Name the metal X.
- Name the metal oxide XO2.
- Which reducing agent can be used to reduce XO2 to obtain metal X?
- Name another metal which can also be extracted by the reduction of its oxide with the above reducing agent.
Which metal can be extracted from the following ore?
Calamine
Some metallic oxides can be reduced by hydrogen, carbon and carbon monoxide and some cannot. Explain.
Give reasons, why aluminum is used in:
painting electric and telegraphic poles
Give the chemical formula of :
Cryolite
Answer the following questions based on the extraction of aluminium from alumina by Hall - Heroult’s Process :
What is the function of cryolite used along with alumina as the electrolyte?
What is meant by refining of metals? Name the three common methods used for refining.
Name:
The allotrope of the non-metal carbon which conducts electricity.
Draw a well-labelled diagram of extraction of Aluminium. Write the anode reaction in electrolytic reduction of Alumina.
How is the method of extraction of metals high up in the reactivity series different from that for metals in the middle? Why can the same process not be applied for them? Name the process used for the extraction of these metals.
In Electrolytic reduction of alumina, Anode : _______ : : Cathode : Graphite lining
Write the name.
The molecular formula of main ore of aluminium –
Explain the following reaction with the balanced equation.
Ferric oxide is reacted with aluminium.
Complete flow chart given below.
Explain Bayer’s process of concentration of bauxite with a chemical equation.
The given reaction shows one of the processes to extract the metals like Iron and Manganese.
\[\ce{MnO2(s) + Al(s) -> Mn(l) + Al2O3(s) + Heat}\]
Give a reason why Aluminium is preferably used in thermite reactions.
