Hydrochloric
acid may be found as a
liquid and a
vapour.
NOTE: When sampling the
odours of unknown
chemicals it is a
good idea to use your hand to gently waft the vapour to your
nose, rather than taking a
big ol' snort.
This is particualrly true if the unknown sample is actually 6M HCl.Alternately, you may remove HCl
vapour from a
contaminated air stream with
activated carbon impregnated with
potassium hydroxide.