Question

How can ammonia gas be used in a chemical laboratory? What are the hazards?

Answer 1

Are you sure it does? When I walk into a lab, usually I can smell that someone has been using ammonia...

Explanation:

Ammonia is a water-like solvent; i.e. it is the hydride of an element that is quite electronegative resulting in polar element-element bond. Given its similarity to water, it should thus have substantial water solubility, and indeed it does....When we buy concentrated solutions of ammonia, (the stuff whose smell makes your eyes water when you open it) this is approx. `15*mol*L^-1` with respect to `NH_3(aq)`. Of course if you flush the sink with copious water, the ammonia will be drained down the sink (with the smell....take that environment!)

Ammonia gas is supplied in a metal cylinder, and can be conveniently collected by condensation with a dry-ice condenser...and this is the basis for the spectacular reaction of sodium with liquid ammonia....which you should be shown in first year uni...

`NH_3(l) + Na(s) rarr NH_2^(-) + Na^(+) +1/2H_2uarr`...

Atop this flask there is an acetone-dry-ice condenser, capable of condensing ammonia (`"normal boiling point"=-33.3` `""^@C`). And please remember this is LIQUID AMMONIA, NOT AQUEOUS AMMONIA! The deep blue colour of the solution is believed to be due to a solvated electron, which has a fairly long lifetime in ammoniacal solution....