Sciencemadness Discussion Board

my copper acetate solutions went cloudy :(

Delta1_05 - 7-12-2016 at 22:45

Hi everyone
This seemed to be the most active chemistry forum I could find, so I decided to ask here. This morning I made a set of copper acetate solutions (in 50% water/50% ethanol) as calibration standards, and they looked great. I went to lunch. When I came back all but the two most concentrated had gone completely cloudy and opaque. The blue colours haven't changed at all, they just went cloudy. Any ideas what's caused this, and how I can prevent it in the future?

DraconicAcid - 7-12-2016 at 22:50

Probably hydrolysis. Add a small amount of acetic acid to prevent or reverse this.

Delta1_05 - 7-12-2016 at 23:56

Ugh, guess I'll have to start again, because I can't change the concentration of these solutions at all. Thanks though, I'll try the acid next time

ave369 - 8-12-2016 at 07:16

It's a salt of a weak acid and a weak base. Yet people still get surprised when hydrolysis occurs.