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NEETChemistryd and f Block Elements

How are dichromates generally prepared?

Options

  1. ABy direct synthesis from chromium metal
  2. BBy reacting chromate with potassium carbonate
  3. CBy fusion of chromite ore with sodium or potassium carbonate in the presence of air
  4. DBy reduction of chromate with hydrogen gas

Correct answer

C. By fusion of chromite ore with sodium or potassium carbonate in the presence of air

Step-by-step solution

Dichromates are generally prepared from chromate, which in turn are obtained by the fusion of chromite ore (FeCr 2 O 4 ) with sodium or potassium carbonate in free access of air.

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