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Manipur Board Class 12 (COHSEM) — free MCQ practice

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Manipur Board Class 12 (COHSEM) subjects

Chemistry (30)

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ChemistryClass 12 ChemistryIsolation of Elements

Try a Manipur Board Class 12 (COHSEM) question

A mineral from which a metal can be extracted profitably is called an:Read the answer and worked solution →The unwanted earthy material mixed with an ore is called:Read the answer and worked solution →The principal ore from which aluminium is extracted is:Read the answer and worked solution →Washing powdered ore in running water so that light gangue floats away is:Read the answer and worked solution →

Worked practice questions

A mineral from which a metal can be extracted profitably is called an:

  1. Ore body
  2. Oil shale
  3. Ash heap
  4. Acid rock
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Correct answer: A. Ore body

1. Not every mineral is worth mining for its metal. 2. Those that are worth it have a special name. 3. They are ore bodies. _Source: syllabus Chemistry Part I, Class XII, General Principles and Processes of Isolation of Elements._

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The unwanted earthy material mixed with an ore is called:

  1. Grate
  2. Gangue
  3. Gauge
  4. Grain
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Correct answer: B. Gangue

1. An ore as mined is never pure. 2. The waste rock around the mineral has a name. 3. That waste is gangue. _Source: syllabus Chemistry Part I, Class XII, General Principles and Processes of Isolation of Elements._

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The principal ore from which aluminium is extracted is:

  1. Bauxite
  2. Barytes
  3. Bornite
  4. Blister
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Correct answer: A. Bauxite

1. One ore is chosen for extracting aluminium. 2. It contains alumina with silica and iron oxides. 3. That ore is bauxite. _Source: syllabus Chemistry Part I, Class XII, General Principles and Processes of Isolation of Elements._

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