CBSE Class 10 Sample Paper Science Solution - For 2024 Boards

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Question 39 (c) - Choice 2 [Case Based] Important

A reddish-brown metal ‘X’, when heated in air, gives a black compound ‘Y’, which when heated in presence of H₂ gas gives ‘X’ back. ‘X’ is refined by the process of electrolysis; this refined form of ‘X’ is used in electrical wiring.

Identify ‘X’ and ‘Y’. Draw a well-labeled diagram to represent the process of refining ‘X’.

 

Answer:

Copper (Cu) is a reddish brown metal, which when heated in air, reacts with oxygen to form black colored copper oxide (CuO). The following reaction takes place:

When CuO is heated in the presence of H 2 , it is again reduced to Cu

Cu is refined by the process of electrolysis.

Refining of metals-01.jpg

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CA Maninder Singh is a Chartered Accountant for the past 14 years and a teacher from the past 18 years. He teaches Science, Economics, Accounting and English at Teachoo