- 1. Fill in the table to indicate the number of atoms of each type in the molecular formula.
- ClF: 1, 1
- CO: 1, 1
- CO₂: 1, 2
- Cl₂O: 2, 1
- PCl₅: 1, 5
- N₂O₅: 2, 5
- 2. Examine the molecular formulas given in Model 1 for various molecular compounds.
- a. How many different elements are present in each compound shown?
- Each compound shown contains exactly two different elements.
- b. Do the compounds combine metals with metals, metals with nonmetals, or nonmetals with nonmetals?
- The compounds combine nonmetals with nonmetals.
- c. Based on your answer to b, what type of bonding must be involved in molecular compounds?
- Covalent bonding must be involved, as it occurs between nonmetal atoms sharing electrons.
- 3. Find all of the compounds in Model 1 that have chlorine and fluorine in them. Explain why the name “chlorine fluoride” is not sufficient to identify a specific compound.
- The compounds containing both chlorine and fluorine are ClF and ClF₅.
- The name “chlorine fluoride” is not sufficient because it does not specify how many atoms of each element are present. Without prefixes like “mono-” or “penta-”, it is impossible to distinguish between ClF (one chlorine, one fluorine) and ClF₅ (one chlorine, five fluorines).
- 4. Assuming that the name of the compound gives a clue to its molecular formula, predict how many atoms each of these prefixes indicates, and provide two examples.
- mono-: Indicates 1 atom. Examples: Carbon monoxide (CO), Chlorine monofluoride (ClF).
- di-: Indicates 2 atoms. Examples: Carbon dioxide (CO₂), Dichlorine monoxide (Cl₂O).
- penta-: Indicates 5 atoms. Examples: Phosphorus pentachloride (PCl₅), Dinitrogen pentoxide (N₂O₅).
Parent Tip: Review the logic above to help your child master the concept of naming molecular compounds worksheet.
