Which of the following is the correct name for the molecular compound CO_2?

• A. Dicarbon monoxide
• B. Carbon dioxide
• C. Carbon monoxide
• D. Carbon oxide

Answer: (B)

Verified step by step guidance

1. Step 1: Identify the elements present in the compound CO_2. Here, the elements are carbon (C) and oxygen (O).
2. Step 2: Determine the number of atoms of each element in the molecule. CO_2 has 1 carbon atom and 2 oxygen atoms.
3. Step 3: Recall the naming rules for molecular (covalent) compounds: use prefixes to indicate the number of atoms (mono-, di-, tri-, etc.), and the second element's name ends with '-ide'.
4. Step 4: Apply the prefixes to the elements: since there is 1 carbon atom, the prefix 'mono-' is usually omitted for the first element; for 2 oxygen atoms, use the prefix 'di-'.
5. Step 5: Combine the names: 'carbon' + 'di-' + 'oxide' gives 'carbon dioxide', which is the correct name for CO_2.