Talk:Ammonia fountain

Latest comment: 11 years ago by 71.187.128.246 in topic Edits by Pwilki

Edits by Pwilki

edit

The edit by Pwilki claiming that the ammonia fountain effect is due to condensation of ammonia vapor was incorrect. It has been removed.

Ammonia is a gas at room temperature (its boiling point is -33 C). The classic ammonia fountain demonstration does not make use of the condensation of a liquid vapor, because ammonia cannot condense at room temperature, and in any case the upper flask contains ammonia at room temperature anyway. The article had it right -- the effect is in fact due to the dissolution of ammonia in water, which reduces the pressure in the upper flask.

However, as noted by Pwilki, it is true that a similar demonstration CAN be performed with a liquid vapor. This fact seemed (to me) to be relevant to the article, since it is a reasonable alternative demonstration, so I left it in. However, such a demonstration is not the ammonia fountain and does not demonstrate the dissolution of ammonia in water. The fountain is still created by reduced pressure, but the pressure is reduced by a different mechanism. 71.187.128.246 (talk) 04:00, 8 December 2012 (UTC)Reply