In organic chemistry,<unk>  serves as a source of chlorine in the Appel reaction.<unk>  made from heavy chlorine-37 has been used in the detection of neutrinos. One specialty use of<unk>  is in stamp collecting, to reveal watermarks on postage stamps without damaging them. A small amount of the liquid is placed on the back of a stamp, sitting in a black glass or obsidian tray. The letters or design of the watermark can then be seen clearly.
Carbon tetrachloride
Arsenic trichloride
Butylated hydroxytoluene
Tetrachlorodecaoxide
Triphenylchloroethylene
Coal tar
Vinyl chloride
Arsenic trioxide