🔍 Key Concepts

• Different refinery fractions produced from coal vs petroleum • Typical alternative names used for aromatic hydrocarbons on a dangerous cargo manifest • Relative volatility and use of naphtha-range products compared with heavier products like tar or middle oils

💭 Think About

• Ask which of these products (toluene, tar, benzene, middle oil) is closest in volatility and lightness to a naphtha-range liquid • Consider which cargo name you would expect to see associated with a highly flammable, lighter fraction rather than a heavy residue • Think about which substances are individual pure chemicals and which are broader mixtures or fractions from distillation

✅ Before You Answer

• Identify which option is a light, volatile aromatic commonly handled as a dangerous cargo • Eliminate any choices that are clearly heavy residues or higher-boiling fractions from coal or petroleum processing • Confirm which term is commonly listed as a UN dangerous good in the naphtha / coal-tar distillate range