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प्रश्न
The electrolysis of alumina involves the use of fluorspar and cryolite to increase the melting point.
विकल्प
Right
Wrong
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उत्तर
The electrolysis of alumina involves the use of fluorspar and cryolite to increase the melting point- Wrong
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संबंधित प्रश्न
Name the following:
The property possessed by metals by which they can be beaten into sheets.
Silver metal does not combine easily with oxygen but silver jewellery tarnishes after some time. How?
Fill in the following blank with suitable word:
The non-metal present in steel is ............
Name one ore of aluminium. Name the aluminium compound present in this ore and write its chemical formula.
Give the name of one ore of iron. Which iron compound is present in this ore? Write its chemical formula.
Describe the extraction of zinc metal from its sulphide ore (zinc blende). Write equations of the reactions involved.
The two metals which can be extracted just by heating their sulphides in air are:
(a) sodium and copper
(b) copper and aluminium
(c) potassium and zinc
(d) mercury and copper
Zinc blende ore can be converted into zinc oxide by the process of:
(a) roasting
(b) hydrogenation
(c) chlorination
(d) calcination
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.
(a) Name the metal X.
(b) Name the metal oxide XO2.
(c) Which reducing agent can be used to reduce XO2 to obtain metal X?
(d) Name another metal which can also be extracted by the reduction of its oxide with the above reducing agent.
Give the principles of the froth floatation process.
Distinguish between ‘roasting’ and ‘calcination’. Which of these two is used for sulphide ores and why?
Name the following:
The substance added to get rid of gangue in the extraction of metal.
Arrange the metals of copper, iron, magnesium, sodium and zinc in the decreasing order of reactivity.
Carbon cannot reduce the oxides of sodium, magnesium, and aluminum to their respective metals. Why? Where are these metals placed in the reactivity series? How are these metals obtained from their ores? Take an example to explain the process of extraction along with chemical equations.
In the electrolytic reduction of alumina, the lining of graphite acts as an anode.
Identify who I am!
Ore of Aluminum- ______
Write the molecular formulae of the following compound.
Sodium aluminate
Explain concept with example/explain with the help of a balanced equation.
Calcination
