On the basis of physical properties, an unknown compound is believed to be one of the following: n-pentane (b.p. 36 \(^{\circ}\) ) 1-pentyne (b.p. \(40^{\circ}\) ) 2 -pentene (b.p. 36 \(^{\circ}\) ) methylene chloride (b.p. \(40^{\circ}\) ) Describe how you would go about finding out which of the possibilities the unknown actually is. Where possible, use simple chemical tests; where necessary, use more elaborate chemical methods like quantitative hydrogenation and cleavage. Tell exactly what you would do and see.

To identify the unknown compound, perform the following series of tests: 1. Test the solubility of the compound in water: If it is insoluble, it is likely an organic compound (n-pentane, 1-pentyne, or 2-pentene); if soluble, it is likely methylene chloride. 2. React the compound with bromine (Br₂): If the reddish-brown color disappears, the compound has a double or triple bond (1-pentyne or 2-pentene); if it remains, the compound is saturated (n-pentane). 3. If a double or triple bond is present, react the compound with Baeyer's reagent (KMnO₄): If the purple color disappears, the compound has a double bond (2-pentene); if it remains, it has a triple bond (1-pentyne). These tests will help identify the unknown compound among the given possibilities.