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प्रश्न
Which of the following metals exist in their native state in nature?
- Cu
- Au
- Zn
- Ag
विकल्प
(i) and (ii)
(ii) and (iii)
(ii) and (iv)
(iii) and (iv)
उत्तर
(ii) and (iv)
Explanation -
Silver and gold are noble metals and in nature, they exist in their free state and not in any combined state as ore.
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संबंधित प्रश्न
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In the extraction of aluminium: Draw the diagram for the extraction of aluminium.
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How are the less reactive metals (which are quite low in the reactivity series) extracted? Explain with the help of an example.
Give the principles of the hydrolytic method.
Complete the following by selecting the correct option from the choices given:
The metal which does not react with water or dilute H2SO4 but reacts with concentrated H2SO4 is _________
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.
Observe the given figure of reactivity series of metals and answer the following questions:
Reactivity series of metals
- Name two metals which react with water.
- Name two moderately reactive metals.
- Name the most highly reactive metal and the most less reactive metal.
Write the molecular formulae of the following compound.
Fluorspar
- Given below are the steps for extraction of copper from its ore. Write the reaction involved.
- Roasting of copper (I) sulphide
- Reduction of copper (I) oxide with copper (I) sulphide.
- Electrolytic refining
- Draw a neat and well labelled diagram for electrolytic refining of copper
