Assertion (A): Actinoids show wide range of oxidation states.
Reason (R): Actinoids are radioactive in nature.
Reason (R): Actinoids are radioactive in nature.
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 B
Solution and Explanation
Both statements must be checked for truth, and then we check whether the Reason actually explains the Assertion.
Step 1:
Assertion: Actinoids show a wide range of oxidation states. This is TRUE. The reason for this is that the 5f, 6d and 7s orbitals have comparable energies, so electrons from these orbitals can take part in bonding.
Step 2:
Reason: Actinoids are radioactive in nature. This is also TRUE.
Step 3:
However, radioactivity is not the cause of the variable oxidation states; the variability is due to the comparable energies of the 5f, 6d and 7s orbitals. So the Reason does not explain the Assertion.
Answer: Option (2) — Both A and R are true, but R is not the correct explanation of A.
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