10. The methods chiefly used for the extraction of lead and tin from their ores, respectively are
(a) self reduction and carbon reduction
(b) self reduction and electrolytic reduction
(c) carbon reduction and self reduction
(d) cyanide process and carbon reduction
answer (a)
Answer explanation : metals are extracted from their ores using different chemical processes. Among them the most important is carbon reduction. Coal has different types of reduction methods like carbon reduction, metal oxide reduction, hydrogen reduction and so forth. This has to be analysed as per the valence layer of electrons in the atom of the metal which is oxide coated in nature. Hence the removal of oxide using self reduction has also been involved .In this method, Lead and tin are immersed in water for more than 30 hours ; then it will automatically get removed of the oxide which bubbles out through water. And this type of oxide removal is used in steel manufacturing since it is cheapest and best.
No comments:
Post a Comment