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NEETChemistryd and f Block Elements

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Mn ₂ O ₇ is an acidic oxide whereas MnO is a basic oxide. Reason (R): In transition metal oxides, as the oxidation state of the metal increases, the ionic character of the metal-oxygen bond increases, which makes the oxide more acidic. In the light of the above statements, choose the most appropria

Options

  1. ABoth Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A)
  2. BBoth Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A)
  3. CAssertion (A) is true but Reason (R) is false
  4. DAssertion (A) is false but Reason (R) is true

Correct answer

C. Assertion (A) is true but Reason (R) is false

Step-by-step solution

Assertion (A) is true: The oxidation state of manganese in Mn ₂ O ₇ is +7, making it an acidic oxide. In MnO , the oxidation state is +2, making it a basic oxide. Reason (R) is false: According to Fajans' rules, as the positive charge (oxidation state) on the metal ion increases, its polarizing power increases. This leads to an increase in the covalent character of the metal-oxygen bond, not the ionic character. The higher covalent character facilitates the release of H ^+ ions in aqueous medium, thereby increasing

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