Creating Lewis Dot Diagrams for elements Neon, Magnesium, Chlorine, and Silicon.

It looks like you've uploaded an image with a chemistry worksheet focused on Lewis dot diagrams and atomic structure for four elements: Neon (Ne), Magnesium (Mg), Chlorine (Cl), and Silicon (Si). The task involves completing information about each element, including protons (P#), electrons (E#), valence electrons, and drawing Lewis dot structures.

Let’s go through each element step by step and fill in the missing data based on periodic table knowledge.

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🔹 1. Neon (Ne)

- Atomic Number: 10 → So, P# = 10, E# = 10
- Electron Configuration: 1s² 2s² 2p⁶ → Outer shell (n=2) has 8 electrons
- Valence Electrons: 8
- Mass #: 20 (given)
- Lewis Dot Diagram: Ne has a full octet → 8 dots around symbol (usually placed as 4 pairs)

✔ Completed:
- P# = 10
- E# = 10
- Valence Electrons = 8
- Atomic #: 10, Mass #: 20

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🔹 2. Magnesium (Mg)

- Atomic Number: 12 → P# = 12, E# = 12
- Electron Configuration: 1s² 2s² 2p⁶ 3s² → Outer shell (n=3) has 2 electrons
- Valence Electrons: 2
- Mass #: 24 (given)
- Lewis Dot Diagram: Mg has 2 valence electrons → 2 dots (not paired)

✔ Completed:
- P# = 12
- E# = 12
- Valence Electrons = 2
- Atomic #: 12, Mass #: 24

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🔹 3. Chlorine (Cl)

- Atomic Number: 17 → P# = 17, E# = 17
- Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁵ → Outer shell (n=3) has 7 electrons
- Valence Electrons: 7
- Mass #: 35 (common isotope; given as 35)
- Lewis Dot Diagram: Cl has 7 valence electrons → 7 dots (one pair + three single dots)

✔ Completed:
- P# = 17
- E# = 17
- Valence Electrons = 7
- Atomic #: 17, Mass #: 35

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🔹 4. Silicon (Si)

- Atomic Number: 14 → P# = 14, E# = 14
- Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p² → Outer shell (n=3) has 4 electrons
- Valence Electrons: 4
- Mass #: 28 (given)
- Lewis Dot Diagram: Si has 4 valence electrons → 4 single dots (no pairs)

✔ Completed:
- P# = 14
- E# = 14
- Valence Electrons = 4
- Atomic #: 14, Mass #: 28

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✔ Summary Table:

| Element | P# | E# | Valence e⁻ | Atomic # | Mass # |
|-------------|----|----|------------|----------|--------|
| Neon | 10 | 10 | 8 | 10 | 20 |
| Magnesium | 12 | 12 | 2 | 12 | 24 |
| Chlorine | 17 | 17 | 7 | 17 | 35 |
| Silicon | 14 | 14 | 4 | 14 | 28 |

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🧪 Creating Lewis Dot Diagrams – Rules Recap:

1. Number of dots = number of valence electrons
2. Place dots around the element’s symbol (top, right, bottom, left), one per side before pairing.
3. Dots are placed singly first, then paired.

#### Example Lewis Structures:
- Mg:
```
.
Mg
.
```
→ Two single dots (valence = 2)

- Cl:
```
..
:Cl:
..
```
→ Seven dots (three sides with pairs, one with single dot — total 7)

- Si:
```
.
Si
.
```
→ Four single dots (one on each side)

> Note: In actual notation, dots are placed on four sides (up, down, left, right). For example:
> - Mg: two dots on one side
> - Si: one dot on each of four sides
> - Cl: three sides have pairs, one side has a single dot

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✔ Final Answer:

All blanks should be filled as follows:

- Neon: P# = 10, E# = 10, Valence e⁻ = 8
- Magnesium: P# = 12, E# = 12, Valence e⁻ = 2
- Chlorine: P# = 17, E# = 17, Valence e⁻ = 7
- Silicon: P# = 14, E# = 14, Valence e⁻ = 4

And draw the corresponding Lewis dot diagrams using the rules above.

Let me know if you'd like a visual version of the Lewis diagrams!