1-Chloronaphthalene is an aromatic compound. It is a colorless, oily liquid which may be used to determine the refractive index

Refractive index

In optics the refractive index or index of refraction of a substance or medium is a measure of the speed of light in that medium. It is expressed as a ratio of the speed of light in vacuum relative to that in the considered medium....

 of crystals by immersion.

This toxic, nonpolar organochlorine compound is sometimes used as a powerful biocide, and is also known as Basileum. It occasionally serves as insecticide and fungicide in the timber floors of shipping containers, where it fulfills the same role as chlordane

Chlordane

Chlordane, or chlordan, is an organochlorine compound that was used as a pesticide. This white solid was sold in the U.S. until 1983 as an insecticide for crops like corn and citrus and on lawns and domestic gardens.-Production and uses:...

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