Covalent Naming worksheet - Free Printable

Absolutely! This worksheet is about naming covalent compounds — molecules formed between two nonmetals, where atoms share electrons. The naming rules for covalent compounds use prefixes to indicate the number of atoms of each element present.

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🔢 Prefixes Used in Covalent Naming:

- 1 = mono- (usually omitted for the first element)
- 2 = di-
- 3 = tri-
- 4 = tetra-
- 5 = penta-
- 6 = hexa-
- 7 = hepta-
- 8 = octa-
- 9 = nona-
- 10 = deca-

> ⚠️ Note: “Mono-” is not used for the first element (e.g., CO is carbon monoxide, not monocarbon monoxide). But it *is* used for the second element if there’s only one atom (e.g., CO → monoxide).

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## ✔ Filled-In Worksheet with Explanations

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➤ First Section: Given Formula → Name

| Covalent formula | Name | Explanation |
|------------------|-------------------------------|-----------|
| SiO₂ | Silicon dioxide | Si = silicon, O₂ = two oxygens → “dioxide”. No prefix on silicon (first element, mono- omitted). |
| NO | Nitrogen monoxide | N = nitrogen, O = one oxygen → “monoxide”. Mono- is needed here for oxygen since it’s the second element and only one atom. |
| PCl₃ | Phosphorus trichloride | P = phosphorus, Cl₃ = three chlorines → “trichloride”. |
| XeF₄ | Xenon tetrafluoride | Xe = xenon, F₄ = four fluorines → “tetrafluoride”. |
| SF₄ | Sulfur tetrafluoride | S = sulfur, F₄ = four fluorines → “tetrafluoride”. |
| N₂O₅ | Dinitrogen pentoxide | N₂ = two nitrogens → “dinitrogen”, O₅ = five oxygens → “pentoxide”. |
| P₄S₃ | Tetraphosphorus trisulfide| P₄ = four phosphorus → “tetraphosphorus”, S₃ = three sulfurs → “trisulfide”. |
| PBr₃ | Phosphorus tribromide | P = phosphorus, Br₃ = three bromines → “tribromide”. |
| CS₂ | Carbon disulfide | C = carbon, S₂ = two sulfurs → “disulfide”. |

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➤ Second Section: Given Name → Formula

| Name | Covalent formula | Explanation |
|---------------------------|------------------|-----------|
| Phosphorous pentabromide | PBr₅ | Phosphorus (P) + penta- (5) bromine atoms → Br₅. So PBr₅. |
| Diphosphorous trioxide | P₂O₃ | Di- (2) phosphorus → P₂, tri- (3) oxygen → O₃. So P₂O₃. |
| Sulfur tribromide | SBr₃ | Sulfur (S) + tri- (3) bromine → Br₃. So SBr₃. |
| Carbon tetrachloride | CCl₄ | Carbon (C) + tetra- (4) chlorine → Cl₄. So CCl₄. |
| Sulfur trioxide | SO₃ | Sulfur (S) + tri- (3) oxygen → O₃. So SO₃. |
| Trisilicon tetranitride | Si₃N₄ | Tri- (3) silicon → Si₃, tetra- (4) nitrogen → N₄. So Si₃N₄. |
| Dinitrogen pentoxide | N₂O₅ | Di- (2) nitrogen → N₂, penta- (5) oxygen → O₅. So N₂O₅. |
| Carbon dioxide | CO₂ | Carbon (C) + di- (2) oxygen → O₂. So CO₂. |

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## 🧠 Quick Tips:

- Always write the element names in order as they appear in the formula.
- Use prefixes for both elements, unless the first element has only one atom (then omit “mono-”).
- The second element ends in “-ide” (e.g., oxide, chloride, sulfide, etc.).

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✔ Your completed worksheet is now accurate and follows standard IUPAC covalent naming rules!

Let me know if you want a printable version or flashcards for practice!