Question

Given below are two statements:
Statement I: Both [Co(NH₃)₆]³⁺ and [CoF₆]^3- complexes are octahedral but differ in their magnetic behaviour.
Statement II: [Co(NH₃)₆]³⁺ is diamagnetic whereas [CoF₆]^3- is paramagnetic.
In the light of the above statements, choose the correct answer from the options given below:

• A. Both Statement I and Statement II are true
• B. Both Statement I and Statement II are false
• C. Statement I is true but Statement II is false
• D. Statement I is false but Statement II is true

Answer 1

The Correct Option is A

Step 1: Analyze [Co(NH₃)₆]³⁺

In this complex, Co³⁺ is in a strong field provided by NH₃ (a strong ligand). The strong field causes the pairing of electrons, making the complex diamagnetic.

Step 2: Analyze [CoF₆]³⁻

In this complex, Co³⁺ is in a weak field provided by F⁻ (a weak ligand). The weak field does not cause pairing of electrons, making the complex paramagnetic.

Step 3: Conclude the Statements 

• Statement I: True — Both complexes are octahedral but differ in magnetic behavior.
• Statement II: True — [Co(NH₃)₆]³⁺ is diamagnetic, and [CoF₆]³⁻ is paramagnetic.

Conclusion

The correct analysis of the magnetic behavior of the complexes confirms that:

Both Statement I and Statement II are true.Step 1: Analyze [Co(NH₃)₆]³⁺

In this complex, Co³⁺ is in a strong field provided by NH₃ (a strong ligand). The strong field causes the pairing of electrons, making the complex diamagnetic.

Step 2: Analyze [CoF₆]³⁻

In this complex, Co³⁺ is in a weak field provided by F⁻ (a weak ligand). The weak field does not cause pairing of electrons, making the complex paramagnetic.

Step 3: Conclude the Statements 

• Statement I: True — Both complexes are octahedral but differ in magnetic behavior.
• Statement II: True — [Co(NH₃)₆]³⁺ is diamagnetic, and [CoF₆]³⁻ is paramagnetic.

Conclusion

The correct analysis of the magnetic behavior of the complexes confirms that:

Both Statement I and Statement II are true.