GENERAL PRINCIPLES AND PROCESSES OF ISOLATION OF ELEMENTS Quiz-20
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The one subject in NEET which is candidates who can easily attain good marks is Chemistry. That's the reason, often, one doesn’t pay notice and choose to compromise it. But if one wants to rank above others, the tip is to be thorough with NEET chemistry concepts. The understanding of reactions and definite basic understanding is what requires major attention in Chemistry but once done it only gets simpler from there. The main focus on the to-do list should be on getting a hang of the NCERT syllabus of NEET chemistry.
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Q1. In the extraction of lead from its ore galena, an important element recovered is:
Solution
Lead extracted from galena contains little Ag. Recovery of Ag from argentiferous lead is made by Parke’s process.
Lead extracted from galena contains little Ag. Recovery of Ag from argentiferous lead is made by Parke’s process.
Q2. Which metal can be purified by distillation?
Solution
Hg has low b. pt. and is purified by distillation.
Hg has low b. pt. and is purified by distillation.
Q3. When copper pyrites is roasted in excess if air, a mixture of CuO+FeO is formed .FeO is present as impurities. This can be removed as slag during reduction of CuO. The flux added to from slag is
Solution
The compounds which combine with impurities preseore (at high temperature) and remove them as afls substance (slag) are known as flux. When basic impurities are present, an acidic flux is used and vice-versa FeO + SiO2 → FeSiO3 Basic impurity acidic flux slag
The compounds which combine with impurities preseore (at high temperature) and remove them as afls substance (slag) are known as flux. When basic impurities are present, an acidic flux is used and vice-versa FeO + SiO2 → FeSiO3 Basic impurity acidic flux slag
Q4. The luster of a metal is due to
Solution
Luster of metals is due to the presence of mobile electrons
Luster of metals is due to the presence of mobile electrons
Q5. During the process of electrolytic refining of copper, some metals present as impurity settle as ‘anode mud’. These are
Solution
During electrolysis, noble metals (inert metals) like Ag, Au and Pt are not affected band separate as anode mud from the impure anode
During electrolysis, noble metals (inert metals) like Ag, Au and Pt are not affected band separate as anode mud from the impure anode
Q6. The method of concentrating the ore which makes use of the difference in density between ore and impurities is called
Solution
Levigation (gravity separation) in based on the difference in the specific gravities of the gangue particles and the ore particles.
Levigation (gravity separation) in based on the difference in the specific gravities of the gangue particles and the ore particles.
Q7.Which metal occurs in free state?
Solution
All are noble metals.
All are noble metals.
Q8. The region in which metals are found in earth is called:
Solution
It is a fact.
It is a fact.
Q9. The correct statement is:
Solution
Cassiterite is a principal ore of tin containing SnO2.
Cassiterite is a principal ore of tin containing SnO2.
Q10. Sulphide ores are generally concentrated by
Solution
Forth floatation method is based on the fact that the surface of sulphide ores is preferentially wetted by oil while that of gangue is wetted by water.
Forth floatation method is based on the fact that the surface of sulphide ores is preferentially wetted by oil while that of gangue is wetted by water.
