COMPASSLearning
RegisterLogin

JEE Main · 2019 · 12 Jan 2019 · Shift 2 · General Principles and Processes of Isolation of Metals

WhatsApp Email
The pair that does NOT require calcination is :
  1. (A)ZnO and MgO✓ Correct
  2. (B)ZnO and
  3. (C) and CaO
  4. (D) and

Answer: (A)

Solution

Calcination heats an ore, usually with little air, to drive off water or and leave the oxide; anything already present as a simple oxide needs none. Both and are already oxides, so that pair requires no calcination, whereas the other pairs hold carbonates or hydrated oxides that must be heated.

JEE Main · 2019 · 12 Jan 2019 · Shift 2 · Single correct option

Practise more: all JEE Main PYQs on General Principles and Processes of Isolation of Metals →

More JEE Main questions on General Principles and Processes of Isolation of Metals

  1. The molar mass of the water insoluble product formed from the fusion of chromite ore with in presence of is ______ .
    JEE Main 2025View solution →
  2. In Hall - Heroult process, the following is used for reducing :-
    JEE Main 2023View solution →
  3. Which of the following metals can be extracted through alkali leaching technique?
    JEE Main 2023View solution →
  4. Which of the following is used as a stabilizer during the concentration of sulphide ores?
    JEE Main 2023View solution →
  5. In the extraction process of copper, the product obtained after carrying out the reactions
    (i)
    (ii) …
    JEE Main 2023View solution →
  6. Given below are two statements :

    Statement-I : In the metallurgy process, sulphide ore is converted to oxide before reduction.

    Statement-II : Oxide ores in general are easier to reduce.

    In the light of the above statements, choose the most appropriate answer from the options g …
    JEE Main 2023View solution →