AP Chemistry style questions on naming molecular compounds

🧪 Quick Study Guide

• ⚛️ Molecular compounds are formed by sharing electrons between atoms (covalent bonds).
• 🔢 Prefixes indicate the number of atoms of each element in the compound (mono-, di-, tri-, tetra-, penta-, hexa-, hepta-, octa-, nona-, deca-).
• 📝 The first element in the formula is named first, using its element name.
• 🔥 The second element is named as an 'ide'. For example, oxygen becomes oxide.
• 💡 'Mono-' is usually omitted for the first element. For example, CO is carbon monoxide, not monocarbon monoxide.
• 📌 When the prefix ends in 'a' or 'o' and the element name begins with 'a' or 'o', the final 'a' or 'o' of the prefix is often dropped (e.g., tetraoxide instead of tetraoxide).

Practice Quiz

1. What is the name of the compound $N_2O_4$?
   1. Nitrogen oxide
   2. Dinitrogen tetroxide
   3. Nitrogen tetroxide
   4. Dinitrogen oxide
2. What is the name of the compound $PCl_5$?
   1. Phosphorus chloride
   2. Monophosphorus pentachloride
   3. Phosphorus pentachloride
   4. Pentachlorophosphorus
3. What is the name of the compound $SF_6$?
   1. Sulfur fluoride
   2. Sulfur hexafluoride
   3. Sulfur(VI) fluoride
   4. Monosulfur hexafluoride
4. What is the name of the compound $CO$?
   1. Carbon oxide
   2. Monocarbon monoxide
   3. Carbon monoxide
   4. Carbon(II) oxide
5. What is the name of the compound $Cl_2O_7$?
   1. Dichlorine heptoxide
   2. Chlorine oxide
   3. Dichlorine oxide
   4. Chlorine heptoxide
6. What is the name of the compound $NO_2$?
   1. Nitrogen oxide
   2. Nitrogen dioxide
   3. Mononitrogen dioxide
   4. Nitrogen(IV) oxide
7. What is the name of the compound $IF_7$?
   1. Iodine fluoride
   2. Iodine heptafluoride
   3. Iodine(VII) fluoride
   4. Monoiodine heptafluoride