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प्रश्न
What is the role of flux in metallurgical processes?
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उत्तर
The ores, even after concentration, contain some gangue. To remove gangue, certain substances are mixed with concentrated ore which combine with the gangue to form a fusible material which is not soluble in molten metal. The substances used are called fluxes.
Fluxes are classified as:
(i) Acidic flux and
(ii) Basic flux. Acidic flux removes basic impurities while basic flux removes acidic impurities.
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संबंधित प्रश्न
Select the process from the following which matches the given description.
(calcination, roasting, pulverisation, smelting)
Heating of the ore in the absence of air to a high temperature.
Choose the correct answer from the options given below:
The main ore used for the extraction of iron is
A. Haematite
B. Calamine
C. Bauxite
D. Cryolite
Name the process by which impure ore of aluminium gets purified by using the concentrated solution of an alkali.
Also give the names of their repective ores ?
Why ‘the food containing iron salts’ should not be cooked in aluminium utensils?
Explain the following term:
Ores
Complete the statement using every given option.
During the extraction of aluminium..............
Use of leaching during the concentration of ore.
Name the following:
The kind of welding in which aluminium powder is used.
Name the following:
Two metals which occur in nature in free state as well as in combined state.
Give composition and uses of the following alloys. Mention the reason for its use.
Bronze
Complete and balance the following equation:
Fe2O3 + → Al2O3 +
Arrange the metals:
calcium, iron, magnesium and sodium in order of their reactivity with water placing the most reactive first.
The following question refer to the extraction of aluminium and iron from their ores:
Iron and aluminum ores both, contain impurities. Explain briefly how these impurities are removed in each case.
Name an alloy of zinc which is used in simple voltaic cells.
From the metals copper, iron, magnesium, sodium and zinc, select a different metal in each case which:
(a) Does not react with dilute hydrochloric acid
(b) Can form 2+ and 3+ ions
(c) Has a hydroxide that reacts with both acid and alkalis.
(d) Does not react with cold water, but reacts with steam when heated.
Find the odd one out of the following and explain your choice : Copper, Lead, Zinc, Mercury
Brass is an alloy of ______.
Name the following:
The ore of zinc containing its sulphide.
Name : The processes involved in Refining of ores
The common method of the extraction of metal from the oxide ore is:-
