Free Printable Lewis Dot Structure Worksheets - Free Printable

You're asking for Lewis structures of 15 molecules/ions from a worksheet. Since I can't draw images, I’ll describe each Lewis structure clearly — including total valence electrons, bonding pattern, lone pairs, and formal charges where needed — so you can easily draw them yourself.

---

1. I₂ (Iodine molecule)

- Valence e⁻: 7 × 2 = 14
- Structure: I — I single bond (2 e⁻)
- Each I has 3 lone pairs (6 e⁻ each → 12 e⁻ total)
- Total: 2 (bond) + 12 (lone pairs) = 14 ✔️
- Nonpolar diatomic.

Lewis:
```
:I — I:
│ │
: :
```
*(Each I has 3 lone pairs — shown as dots or lines)*

---

2. HBr (Hydrogen bromide)

- Valence e⁻: H=1, Br=7 → total 8
- Bond: H — Br single bond (2 e⁻)
- Br has 3 lone pairs (6 e⁻)
- Total: 2 + 6 = 8 ✔️

Lewis:
```
H — Br:
│
:
```
*(Br has 3 lone pairs; H has none)*

---

3. CS₂ (Carbon disulfide)

- Valence e⁻: C=4, S=6×2=12 → total 16
- Structure: S=C=S (double bonds)
- Each S has 2 lone pairs (4 e⁻ each → 8 e⁻)
- C has no lone pairs
- Total: 8 (bonds) + 8 (lone pairs) = 16 ✔️
- Linear, like CO₂.

Lewis:
```
:S=C=S:
│ │
: :
```
*(Each S has 2 lone pairs)*

---

4. O₃ (Ozone)

- Valence e⁻: 6 × 3 = 18
- Resonance structure: central O bonded to two O atoms
- One O=O double bond, one O–O single bond (with charge separation)
- Central O: 1 lone pair, +1 formal charge
- Single-bonded O: 3 lone pairs, –1 formal charge
- Double-bonded O: 2 lone pairs, 0 formal charge

Lewis (one resonance form):
```
[O=O⁺—O⁻] ↔ [⁻O—O⁺=O]
```
*(Better drawn with one double bond, one single bond, and charges)*

Total e⁻: 8 in bonds + 10 in lone pairs = 18 ✔️

---

5. SiH₄ (Silane)

- Valence e⁻: Si=4, H=1×4=4 → total 8
- Tetrahedral: Si central, 4 single bonds to H
- No lone pairs on Si
- Each H has no lone pairs

Lewis:
```
H
│
H — Si — H
│
H
```
*(All bonds single; no lone pairs anywhere)*

---

6. NO₃⁻ (Nitrate ion)

- Valence e⁻: N=5, O=6×3=18, +1 for charge → total 24
- Resonance: 3 equivalent structures
- Central N bonded to 3 O atoms
- One N=O double bond, two N–O single bonds (each with O⁻)
- Formal charges: N=+1, single-bonded O=–1, double-bonded O=0
- Average bond order = 1.33

Lewis (one resonance form):
```
[O⁻]
│
[O=N⁺—O⁻] (with lone pairs added)
```
*(Each O has 3 lone pairs except double-bonded O has 2)*

Total e⁻: 8 in bonds + 16 in lone pairs = 24 ✔️

---

7. C₂H₆ (Ethane)

- Valence e⁻: C=4×2=8, H=1×6=6 → total 14
- Structure: C–C single bond, each C bonded to 3 H
- All single bonds
- No lone pairs

Lewis:
```
H H
│ │
H — C — C — H
│ │
H H
```

---

8. CH₂Cl₂ (Dichloromethane)

- Valence e⁻: C=4, H=1×2=2, Cl=7×2=14 → total 20
- Tetrahedral: C central, bonded to 2H and 2Cl
- All single bonds
- Each Cl has 3 lone pairs (6 e⁻ each → 12 e⁻)

Lewis:
```
H
│
Cl — C — Cl
│
H
```
*(Add 3 lone pairs on each Cl)*

Total e⁻: 8 in bonds + 12 in lone pairs = 20 ✔️

---

9. SO₄²⁻ (Sulfate ion)

- Valence e⁻: S=6, O=6×4=24, +2 for charge → total 32
- Resonance: 4 equivalent S–O bonds (average bond order 1.5)
- Two common ways: 2 double bonds + 2 single bonds (with O⁻), OR expanded octet with 4 single bonds and S with +2 charge (less accurate)
- Better: S with 2 double bonds to O, 2 single bonds to O⁻
- Formal charges: S=0, double-bonded O=0, single-bonded O=–1

Lewis (one resonance form):
```
[O⁻] [O⁻]
│ │
O=S=O (but actually tetrahedral)
```
*(Actually 3D tetrahedral; each O has 3 lone pairs except double-bonded have 2)*

Total e⁻: 16 in bonds + 16 in lone pairs = 32 ✔️

---

10. I₃⁻ (Triiodide ion)

- Valence e⁻: I=7×3=21, +1 for charge → 22
- Linear: central I bonded to two terminal I
- Central I: 3 lone pairs, 2 bonds → 10 e⁻ (expanded octet)
- Terminal I: 3 lone pairs + 1 bond → 8 e⁻
- Formal charges: central I=–1, terminal I=0

Lewis:
```
[I — I — I]⁻
│ │ │
: : :
```
*(Central I has 3 lone pairs, terminal I have 3 each)*

Total e⁻: 4 in bonds + 18 in lone pairs = 22 ✔️

---

11. BF₃ (Boron trifluoride)

- Valence e⁻: B=3, F=7×3=21 → total 24
- Trigonal planar: B central, 3 single bonds to F
- B has no lone pairs (electron-deficient)
- Each F has 3 lone pairs (18 e⁻)

Lewis:
```
F
│
F — B — F
```
*(Add 3 lone pairs on each F)*

Total e⁻: 6 in bonds + 18 in lone pairs = 24 ✔️

---

12. PH₃ (Phosphine)

- Valence e⁻: P=5, H=1×3=3 → total 8
- Pyramidal: P central, 3 single bonds to H
- P has 1 lone pair (2 e⁻)
- Each H has no lone pairs

Lewis:
```
H
│
H — P — H
│
:
```
*(P has 1 lone pair)*

Total e⁻: 6 in bonds + 2 in lone pair = 8 ✔️

---

13. OF₂ (Oxygen difluoride)

- Valence e⁻: O=6, F=7×2=14 → total 20
- Bent: O central, 2 single bonds to F
- O has 2 lone pairs (4 e⁻)
- Each F has 3 lone pairs (6 e⁻ each → 12 e⁻)

Lewis:
```
F
│
F — O —
│
:
```
*(O has 2 lone pairs; each F has 3)*

Total e⁻: 4 in bonds + 16 in lone pairs = 20 ✔️

---

14. PO₃³⁻ (Phosphite ion)

- Valence e⁻: P=5, O=6×3=18, +3 for charge → total 26
- P central, 3 single bonds to O (each O⁻)
- P has 1 lone pair
- Each O has 3 lone pairs

Lewis:
```
[O⁻]
│
[O⁻—P—O⁻]
│
:
```
*(P has 1 lone pair; each O has 3 lone pairs and –1 charge)*

Total e⁻: 6 in bonds + 20 in lone pairs = 26 ✔️

---

15. PO₄³⁻ (Phosphate ion)

- Valence e⁻: P=5, O=6×4=24, +3 for charge → total 32
- Tetrahedral: P central, 4 single bonds to O (each O⁻)
- P has no lone pairs
- Each O has 3 lone pairs (24 e⁻)

Lewis:
```
[O⁻]
│
[O⁻—P—O⁻]
│
[O⁻]
```
*(Each O has 3 lone pairs and –1 charge; P has +1 formal charge — but resonance distributes it)*

Total e⁻: 8 in bonds + 24 in lone pairs = 32 ✔️

*(Note: Actual structure has resonance with some P=O bonds, but for intro level, 4 single bonds with O⁻ is acceptable.)*

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## ✔ Summary Tips:
- Count total valence electrons first.
- Place least electronegative atom in center (except H).
- Make single bonds first, then add lone pairs to satisfy octet (except H, which needs 2).
- If not enough electrons, form double/triple bonds.
- Check formal charges — minimize them, negative on more electronegative atoms.
- For ions, enclose in brackets with charge.

You can now draw all 15 structures using these descriptions!

Let me know if you want any one drawn step-by-step or need help with formal charges!