Free Printable Naming Molecular Compounds Worksheets - Free Printable

Worksheet: Naming Molecular Compounds

#### Part 1: Write the formulas for each of the following covalent compounds.

To solve this part, we need to use the prefixes in the names to determine the number of atoms of each element in the compound. Here are the solutions:

1. sulfur tetroxide
- Prefix "tetra-" means 4.
- Formula: SO₄

2. phosphorus trifluoride
- Prefix "tri-" means 3.
- Formula: PF₃

3. iodine monobromide
- Prefix "mono-" means 1.
- Formula: IBr

4. silicon tetrahydride
- Prefix "tetra-" means 4.
- Formula: SiH₄

5. selenium dioxide
- No prefix for oxygen means 2.
- Formula: SeO₂

6. oxygen dichloride
- Prefix "di-" means 2.
- Formula: OCl₂

7. bromine pentachloride
- Prefix "penta-" means 5.
- Formula: BrCl₅

8. oxygen difluoride
- Prefix "di-" means 2.
- Formula: OF₂

9. phosphorus pentachloride
- Prefix "penta-" means 5.
- Formula: PCl₅

10. nitrogen monoxide
- Prefix "mono-" means 1.
- Formula: NO

11. dinitrogen tetroxide
- Prefix "di-" means 2 for nitrogen, and "tetra-" means 4 for oxygen.
- Formula: N₂O₄

12. diphosphorus pentoxide
- Prefix "di-" means 2 for phosphorus, and "penta-" means 5 for oxygen.
- Formula: P₂O₅

13. disulfur difluoride
- Prefix "di-" means 2 for both sulfur and fluorine.
- Formula: S₂F₂

14. tetraphosphorus trisulfide
- Prefix "tetra-" means 4 for phosphorus, and "tri-" means 3 for sulfur.
- Formula: P₄S₃

15. dinitrogen tetrachloride
- Prefix "di-" means 2 for nitrogen, and "tetra-" means 4 for chlorine.
- Formula: N₂Cl₄

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#### Part 2: Name each of the following covalent compounds.

To solve this part, we need to use the subscripts in the formulas to determine the prefixes for the names. Here are the solutions:

1. CO₂
- Carbon (C) has no prefix (implied 1).
- Oxygen (O) has a subscript of 2, so the prefix is "di-".
- Name: carbon dioxide

2. SO₃
- Sulfur (S) has no prefix (implied 1).
- Oxygen (O) has a subscript of 3, so the prefix is "tri-".
- Name: sulfur trioxide

3. N₂O₃
- Nitrogen (N) has a subscript of 2, so the prefix is "di-".
- Oxygen (O) has a subscript of 3, so the prefix is "tri-".
- Name: dinitrogen trioxide

4. N₂O₅
- Nitrogen (N) has a subscript of 2, so the prefix is "di-".
- Oxygen (O) has a subscript of 5, so the prefix is "penta-".
- Name: dinitrogen pentoxide

5. PCl₃
- Phosphorus (P) has no prefix (implied 1).
- Chlorine (Cl) has a subscript of 3, so the prefix is "tri-".
- Name: phosphorus trichloride

6. NH₃
- Nitrogen (N) has no prefix (implied 1).
- Hydrogen (H) has a subscript of 3, so the prefix is "tri-".
- Name: nitrogen trihydride (or more commonly, ammonia)

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Final Answers:

#### Part 1: Formulas
1. SO₄
2. PF₃
3. IBr
4. SiH₄
5. SeO₂
6. OCl₂
7. BrCl₅
8. OF₂
9. PCl₅
10. NO
11. N₂O₄
12. P₂O₅
13. S₂F₂
14. P₄S₃
15. N₂Cl₄

#### Part 2: Names
1. carbon dioxide
2. sulfur trioxide
3. dinitrogen trioxide
4. dinitrogen pentoxide
5. phosphorus trichloride
6. nitrogen trihydride (or ammonia)

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Final Answer Box:
\[
\boxed{
\begin{array}{ll}
\text{Part 1:} & \text{Part 2:} \\
1. \ SO_4 & 1. \ \text{carbon dioxide} \\
2. \ PF_3 & 2. \ \text{sulfur trioxide} \\
3. \ IBr & 3. \ \text{dinitrogen trioxide} \\
4. \ SiH_4 & 4. \ \text{dinitrogen pentoxide} \\
5. \ SeO_2 & 5. \ \text{phosphorus trichloride} \\
6. \ OCl_2 & 6. \ \text{nitrogen trihydride (ammonia)} \\
7. \ BrCl_5 & \\
8. \ OF_2 & \\
9. \ PCl_5 & \\
10. \ NO & \\
11. \ N_2O_4 & \\
12. \ P_2O_5 & \\
13. \ S_2F_2 & \\
14. \ P_4S_3 & \\
15. \ N_2Cl_4 & \\
\end{array}
}
\]