What is the correct name for the molecular compound N2O5?

• A. nitrogen dioxide
• B. dinitrogen dioxide
• C. dinitrogen pentoxide
• D. nitrogen pentoxide

Answer: (C)

Verified step by step guidance

1. Identify the elements present in the compound N2O5. Here, the elements are nitrogen (N) and oxygen (O).
2. Determine the number of atoms of each element in the molecule. N2O5 has 2 nitrogen atoms and 5 oxygen atoms.
3. Recall the naming rules for molecular (covalent) compounds: use prefixes to indicate the number of atoms of each element. The prefixes are: mono- (1), di- (2), tri- (3), tetra- (4), penta- (5), etc.
4. Apply the prefixes to the element names. For nitrogen, use 'di-' because there are 2 atoms, and for oxygen, use 'penta-' because there are 5 atoms. The second element's name ends with '-ide', so oxygen becomes 'oxide'.
5. Combine the prefixes and element names to form the full name: 'dinitrogen pentoxide'. This is the correct systematic name for N2O5.