To determine the incorrect electronic arrangement from the given options, we will analyze each configuration step by step.
### Step 1: Understand the Electronic Configuration
The electronic configuration of an atom describes how electrons are distributed among the various atomic orbitals. The general order of filling is based on the Aufbau principle, which states that electrons occupy the lowest energy orbitals first.
### Step 2: List the Given Options
The options provided are:
1. 2, 8, 13
2. 1, 2, 8, 12
3. 2, 2, 8, 8
4. 1, 2, 8, 8
### Step 3: Analyze Each Configuration
1. **Configuration 2, 8, 13:**
- This implies 2 electrons in the first shell (K), 8 in the second (L), and 13 in the third (M).
- The maximum number of electrons in the third shell is 18 (2 in 3s and 10 in 3p).
- Therefore, this configuration is possible.
2. **Configuration 1, 2, 8, 12:**
- This implies 1 electron in the first shell (K), 2 in the second (L), 8 in the third (M), and 12 in the fourth (N).
- The fourth shell can hold a maximum of 32 electrons, but we need to check the filling order.
- The filling order should be 4s before 3d. This configuration is also possible.
3. **Configuration 2, 2, 8, 8:**
- This implies 2 electrons in the first shell (K), 2 in the second (L), 8 in the third (M), and 8 in the fourth (N).
- The second shell can hold a maximum of 8 electrons, and the third shell can hold a maximum of 18.
- This configuration is also possible.
4. **Configuration 1, 2, 8, 8:**
- This implies 1 electron in the first shell (K), 2 in the second (L), 8 in the third (M), and 8 in the fourth (N).
- The filling order should be 4s before 3d. This configuration is also possible.
### Step 4: Identify the Incorrect Configuration
After analyzing all configurations, the one that does not follow the correct filling order or exceeds the maximum capacity of the shells is:
- **Configuration 2, 8, 13** is incorrect because the third shell cannot hold 13 electrons when it should be filled as 2 in 3s and 10 in 3p, totaling 12.
### Conclusion
The incorrect electronic arrangement is **2, 8, 13**.
---
