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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
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
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Also give the names of their repective ores ?
How does aluminum react with the Base ?
State the use of:
wrought Iron
State the use of:
hard steel
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Name the following:
The chief metal present in magnalium and duralumin
Give composition and uses of the following alloys. Mention the reason for its use.
Solder
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Al + N2 →
Name an alloy of zinc which is used in simple voltaic cells.
What is added to steel to make it stainless steel?
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.
Write the equation for the reaction of zinc with following: Dilute sulphuric acid
A to F below relate to the source and extraction of either zinc or aluminium.
- Bauxite
- Coke
- Cryolite
- Froth floatation
- Sodium hydroxide solution
- Zinc blende
Write the formula of cryolite.
In the Wilfley table method, the particles of gangue are separated by __________ separation method.
Which of the following statements are correct?
(i) A depressant prevents certain type of particle to come to the froth.
(ii) Copper matte contains \[\ce{Cu2S}\] and \[\ce{ZnS}\].
(iii) The solidified copper obtained from reverberatory furnace has blistered appearance due to evolution of \[\ce{SO2}\] during the extraction.
(iv) Zinc can be extracted by self-reduction.
