Pine forests, smell

It may seem strange to classify a type of bond as a functional group, but you will see later that C=C double bonds impart reactivity to an organic molecule just as functional groups consisting of, say, oxygen or nitrogen atoms do. Some of the compounds produced by plants and used by perfumers are alkenes (see Chapter 1). For example, pinene has a smell evocative of pine forests, while limonene smells of citrus fruits. 

Where on the earth can you go to be totally separate from hydrocarbons Almost nowhere. How about deep in dense woods No, the wonderful smell of a pine forest is from naturally occurring hydrocarbons called (for good reasons) pinenes. On an all-wooden boat on an ocean, out of sight of land Perhaps, if the boat isn t painted with an oil-based paint commonly used on marine vessels. In the middle of a desert, on top of Mount Everest, or at the North or South Pole Perhaps, but wherever it is, you d better be dressed in clothing that was manufactured in the 18th century ... 

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