The orbital diagram in which Hund's rule and Aufbau principle is violated is

Options

A.
B.
C.
D.

Answer

To determine which orbital diagram violates Hund's rule and the Aufbau principle, we need to understand what these principles state:

1. **Aufbau Principle**: This principle states that electrons occupy the lowest energy orbitals first before moving to higher energy orbitals. In simpler terms, we fill the orbitals in order of increasing energy.

2. **Hund's Rule**: This rule states that for degenerate orbitals (orbitals of the same energy), one electron must be placed in each orbital before any pairing occurs. This means that all orbitals in a subshell must have one electron before any of them can have two.

Now, let's analyze the options provided in the question step by step:

### Step 1: Analyze the First Option
- In the first option, if we observe that there are paired electrons in an orbital before all orbitals in the subshell are filled, this violates Hund's rule.
- **Conclusion**: This option is incorrect.

### Step 2: Analyze the Second Option
- The second option shows that there is one electron in the s subshell, and then electrons are being placed in the p subshell without completely filling the s subshell.
- This violates the Aufbau principle because we should fill the s subshell completely before moving to the p subshell.
- **Conclusion**: This option is incorrect.

### Step 3: Analyze the Third Option
- In the third option, if both electrons in a subshell are spinning in the same direction (both clockwise), this violates Hund's rule, which states that one must be clockwise and the other must be anticlockwise.
- **Conclusion**: This option is incorrect.

### Step 4: Analyze the Fourth Option
- In the fourth option, if the subshell is not fully filled before moving to a higher energy subshell, this again violates the Aufbau principle.
- **Conclusion**: This option is incorrect.

### Final Conclusion
After analyzing all the options, we find that all provided diagrams violate either Hund's rule or the Aufbau principle. Therefore, none of the options correctly follow the rules of electron configuration.