The electron distribution in an aluminium atom is

Options

A. `2, 8, 3`
B. `2, 8, 2`
C. `8, 2, 3`
D. `2, 3, 8`

Explanation

To determine the electron distribution in an aluminum atom, we need to follow these steps:

### Step 1: Identify the Atomic Number
The atomic number of aluminum (Al) is 13. This means that an aluminum atom has 13 electrons.

### Step 2: Understand Electron Shells
Electrons are arranged in shells around the nucleus. The first shell (K shell) can hold a maximum of 2 electrons, the second shell (L shell) can hold a maximum of 8 electrons, and the third shell (M shell) can hold up to 18 electrons, but we will only fill it with the remaining electrons in this case.

### Step 3: Fill the K Shell
The K shell can hold 2 electrons. Therefore, we place 2 electrons in the K shell:
- K shell: 2 electrons

### Step 4: Fill the L Shell
Next, we fill the L shell, which can hold 8 electrons. After placing 2 electrons in the K shell, we have 11 electrons left (13 - 2 = 11). We can fill the L shell with 8 electrons:
- L shell: 8 electrons

### Step 5: Fill the M Shell
Now, we have 3 electrons remaining (11 - 8 = 3). These will go into the M shell:
- M shell: 3 electrons

### Step 6: Write the Electron Configuration
Now we can write the electron distribution for an aluminum atom:
- K shell: 2 electrons
- L shell: 8 electrons
- M shell: 3 electrons

Thus, the electron distribution in an aluminum atom can be represented as:
- Electron Configuration: 2, 8, 3

### Final Answer
The electron distribution in an aluminum atom is 2, 8, 3.

---