Assertion (A): Transition metals show their highest oxidation state with oxygen.
Reason (R): The ability of oxygen to form multiple bonds to metals.
Reason (R): The ability of oxygen to form multiple bonds to metals.
Show Hint
- Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
- Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- Assertion (A) is true, but Reason (R) is false.
- Assertion (A) is false, but Reason (R) is true.
The Correct Option is A
Solution and Explanation
Step 1: Check the Assertion
The highest oxidation states of transition metals are indeed seen in their oxides. For example manganese is $+7$ in $\mathrm{Mn_2O_7}$ and osmium is $+8$ in $\mathrm{OsO_4}$. So the Assertion is true.
Step 2: Check the Reason
Oxygen is small and strongly electron-pulling, and it can also form double bonds to the metal. These extra $\mathrm{M=O}$ bonds let the metal share more of its electrons and so reach a very high oxidation state. So the Reason is true.
Step 3: Do they connect
This ability of oxygen to form multiple bonds is exactly the reason it can pull metals up to their highest states, so the Reason correctly explains the Assertion.
Answer: Option (A), both are true and R correctly explains A.
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