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प्रश्न
Which metal becomes black in the presence of hydrogen sulphide gas in air?
उत्तर
Silver metal becomes black in the presence of hydrogen sulphide gas in the air. Silver reacts with hydrogen sulphide gas in the air and forms a thin black layer of silver sulphide (Ag2S) on it. Therefore, silver jewellery or ornaments become dull due to the formation of silver sulphide coating on their surface.
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संबंधित प्रश्न
An ore of manganese metal is:
(a) bauxite
(b) haematite
(c) cuprite
(d) pyrolusite
Which metal can be extracted from the following ore?
Haematite
Give the chemical formula of :
Bauxite
Answer the following questions based on the extraction of aluminium from alumina by Hall - Heroult’s Process :
What is the function of cryolite used along with alumina as the electrolyte?
Answer the following questions based on the extraction of aluminium from alumina by Hall - Heroult’s Process :
Why is powdered coke sprinkled on top of the electrolyte?
Correct the following statement :
Copper reacts with nitric acid to produce nitrogen dioxide.
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.
If Cu, Fe, Zn, Al elements are arranged in increasing order of their reactivity then the correct order would be which of the following?
Explain the concept of Calcination.
Complete flow chart given below.
