Fluorine possesses an odor which M. Moissan compares to a mixture of
hypochlorous acid and nitrogen peroxide, but this odor is usually
masked by that of the ozone which it always produces in moist air,
owing to its decomposition of the water vapor. It produces most
serious irritation of the bronchial tubes and mucous membrane of the
nasal cavities, the effects of which are persistent for quite a
fortnight.
When examined in a thickness of one meter, it is seen to possess a
greenish yellow color, but paler, and containing more of yellow, than
that of chlorine. In such a layer, fluorine does not present any
absorption bands. Its spectrum exhibits thirteen bright, lines in the
red, between wave lengths 744 and 623. Their positions and relative
intensities are as follows:
[lambda] = 744 very feeble. | [lambda] = 685.5 feeble
740 " | 683.5 "
734 " | 677 strong
714 feeble. | 640.5 "
704 " | 634 "
691 " | 623 "
687.5 " |
At a temperature of -95° at ordinary atmospheric pressure, fluorine
remains gaseous, no sign of liquefaction having been observed.