•A precipitate is an insoluble solid that forms when two or more solutions are mixed.
•It appears cloudy in solution since the small suspended particles scatter light.
•Precipitates form when the ions experience an electrostatic attraction to each other and they stick together, forming crystals.
A precipitate can be removed by filtration.
•An ionic equation only shows the reacting species.
•Eg. Barium nitrate reacts with Sodium sulfate to produce the precipitate Barium sulfate.
Ba(NO3)2 (aq) + Na2SO4 (aq) --> BaSO4 (s) + 2NaNO3 (aq)
Showing individual ions:
Ba2+ (aq) + 2NO3 2- (aq) + 2Na+ (aq) + SO4 2- (aq) ---> BaSO4 (s) + 2Na+ (aq) + 2NO3 2- (aq)
Ionic equation- only shows reacting species:
Ba2+ (aq) + SO4 2- (aq) ---> BaSO4 (s)
Silver chloride precipitate courtesy of By Luisbrudna - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=40139259