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प्रश्न
How is the method of extraction of metals high up in the reactivity series different from that for metals in the middle? Why can the same process not be applied for them? Name the process used for the extraction of these metals.
उत्तर
The metals high up in the reactivity series generally occur in the form of their oxides which are quite stable and cannot be extracted by reducing the oxides with carbon. On the other hand, the metals in the middle of the reactivity series occur in the form of carbonates and sulphides which are first converted into oxides by various methods and then into metals.
The same process can not be applied for them because of the difference in their reactivity due to which they occur in different forms as ores.
The process used for the extraction of highly reactive metals is electrolytic reduction.
The process used for the extraction of moderately reactive metals is calcination or roasting followed by reduction.
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संबंधित प्रश्न
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