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NEETChemistryd and f Block Elements

When an orange solution containing Cr 2 O 7 2– ion is treated with an alkali, a yellow solution is formed, and when H + ions are added to the yellow solution, an orange solution is obtained. Explain why does this happen?

Options

  1. ACr 2 O 7 2– ion undergoes redox reactions with both alkali and acid.
  2. BThe pH of the solution affects the equilibrium between Cr 2 O 7 2– and CrO 4 2– ions.
  3. CThe addition of H + ions shifts the equilibrium towards theCr 2 O 7 2– ion.
  4. DThe alkali changes the coordination number of chromium.

Correct answer

B. The pH of the solution affects the equilibrium between Cr 2 O 7 2– and CrO 4 2– ions.

Step-by-step solution

Correct Option is : (B) The pH of the solution affects the equilibrium between Cr 2 O 7 2– and CrO 4 2– ions.

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