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CG PET CN and OS — practice questions

Explore 1 free CN and OS questions in CG PET Chemistry. Open each question or exercise to read its content, reference answers and available explanation.

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In the complex $K_3[Cr(C_2O_4)_3]$, the coordination number and oxidation state of Cr respectively are:Read the answer and worked solution →

Worked practice questions

In the complex $K_3[Cr(C_2O_4)_3]$, the coordination number and oxidation state of Cr respectively are:

  1. 3 and +3
  2. 6 and +3
  3. 6 and +6
  4. 3 and +6
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Correct answer: B. 6 and +3

Each oxalate ($C_2O_4^{2-}$) is bidentate (2 donor O atoms). Three oxalates → 6 donor atoms → CN = 6. Charge: Cr + 3(-2) = -3 (matching 3K⁺) ⇒ Cr = +3.

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More Chemistry topics

Ideal and Non-Ideal SolutionsIdeal SolutionsNon-Ideal SolutionsReactions in Aqueous SolutionElectrochemistryElectrochemical SeriesCoordination CompoundsSolutions