Assertion : Inner orbital complexes are low spin complexes .
Reason : In low spin complexes , inner d-orbital (3d) is used in hybridisation .

Options

A. If both Assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. if both assertion and reason are false

Explanation

To analyze the assertion and reason provided in the question, we will break it down step by step.

### Step 1: Understanding the Assertion
The assertion states that "Inner orbital complexes are low spin complexes."

**Explanation**:
Inner orbital complexes are formed when the central metal ion uses its inner d-orbitals (like 4d or 5d) for hybridization. In these complexes, the presence of strong field ligands causes the electrons in the d-orbitals to pair up before they occupy higher energy orbitals. This pairing leads to a lower number of unpaired electrons, which is characteristic of low spin complexes.

### Step 2: Understanding the Reason
The reason states that "In low spin complexes, inner d-orbital (3d) is used in hybridization."

**Explanation**:
In low spin complexes, particularly those involving transition metals, strong field ligands lead to the pairing of electrons in the lower energy d-orbitals. This means that the inner d-orbitals (like 3d) are used in hybridization. For example, in complexes like [Ni(CN)₄]²⁻, the strong field ligand CN⁻ causes the electrons to pair up in the 3d orbitals, leading to dsp² hybridization.

### Step 3: Conclusion
Both the assertion and the reason are true. The assertion correctly identifies that inner orbital complexes are low spin complexes, and the reason accurately describes the hybridization process in these complexes.

### Final Answer
Both the assertion and the reason are true, and the reason correctly explains the assertion.

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