The electronic arrangement of an atom with two electrons in the first shell is called _________ if the first shell is the valence shell.

Explanation

To solve the question regarding the electronic arrangement of an atom with two electrons in the first shell, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Electron Shells**:
- Atoms consist of a nucleus surrounded by electrons that are arranged in different energy levels or shells. The first shell, also known as the K shell, can hold a maximum of 2 electrons.

2. **Identify the Number of Electrons**:
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