Question 42 In which electron-orbital diagram is Hund's Rule violated? I [Ar II. [Ar) III. [Ar] IV. [Ar] ↑↓ 4s O IV. ◯WII. ◯l. ↑↑ 4s ◯ll. 4s ↑↓ 4s FF1 3d 소소소 3d ↑ 11 ↑↑↑↑↑ 3d = 一
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![**Electron-Orbital Diagram Question**
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### Question 42
**In which electron-orbital diagram is Hund's Rule violated?**
Diagram options:
- **I.**
\[ \text{[Ar]} \quad \uparrow\downarrow \quad 4s \quad \uparrow\downarrow \quad \uparrow \quad \uparrow \quad \uparrow \quad \quad \quad 3d \]
- **II.**
\[ \text{[Ar]} \quad \uparrow\downarrow \quad 4s \quad \uparrow \quad \uparrow \quad \uparrow \quad \uparrow \quad \uparrow \quad 3d \]
- **III.**
\[ \text{[Ar]} \quad \uparrow\downarrow \quad 4s \quad \uparrow \quad \uparrow \quad \uparrow \quad \quad \quad \quad \quad \quad 3d \]
- **IV.**
\[ \text{[Ar]} \quad \uparrow \quad \downarrow \quad 4s \quad \uparrow\downarrow \quad \uparrow \quad \uparrow \quad \uarrow \quad 3d \]
Answer choices:
- ( ) IV.
- ( ) III.
- ( ) I.
- ( ) II.
### Explanation
To determine which electron-orbital diagram violates Hund's Rule, we need to understand Hund's Rule:
**Hund's Rule** states that electrons must occupy every orbital singly before any orbital is doubly occupied. Additionally, all electrons in singly occupied orbitals must have the same spin.
Diagram-by-diagram analysis:
- **Diagram I** violates Hund's Rule because the 3d orbitals are doubly occupied before all orbitals are singly occupied.
- **Diagram II** does not violate Hund's Rule as all orbitals in 3d are singly occupied with the same spin.
- **Diagram III** does not violate Hund's Rule because it adheres to the principle of singly occupying each 3d orbital before any pairing occurs.
- **Diagram IV** also violates Hund's Rule because the 4s orbital should be doubly occupied with the correct spin alignment.
After this analysis, it's clear that **Diagram I** is the one in which Hund's Rule is violated.](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2F985fbbf0-f8fa-4c87-a1a5-f926559935c9%2F2c8e8d39-ec1a-4e2b-899c-ecdd7948c89c%2F778sigx_processed.jpeg&w=3840&q=75)
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