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The oxidation states of Cr in [ C r H 2 O ) 6 C l 3 , [ C r C 6 H 6 ) 2 and K 2 [ C r ( C N ) 2 O ) 2 O 2 N H 3 respectively are

Options

  1. A+3, +4 and +6
  2. B+3, +2 and +4
  3. C+3, 0 and +6
  4. D+3, 0 and +4

Correct answer

C. +3, 0 and +6

Step-by-step solution

[ C r H 2 O ) 6 C l 3 : x + 6 × 0 + 3 × - 1 = 0 x = + 3 [ C r C 6 H 6 ) 2 : x + 2 × 0 x = 0 K 2 [ C r C N ) 2 O 2 O 2 N H 3 2 × ( + 1 ) + x + 2 × ( - 1 ) + 2 × ( - 2 ) + 2 × ( - 1 ) + 0 = 0 2 + x - 2 - 4 - 2 = 0 x = + 6

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