Re: fresh chemicals

Mac Legrandi (fontpro@usa.net)
Mon, 09 Feb 1998 22:45:25 -0800

>You know, it really depends on the particular chemical, but generally
>speaking, heat and humidity hasten the compounds demise. I have many jars
>that are about twenty years old, and can say as a rule of thumb if they
>have not changed their appearance they should be fine- decomposition
>almost always involves a change in appearance. The only compound that I
>have that seems to have changed is some pyrochatechin which has gone
>greyish, but I received it as a gift and not in its original container.

So if I have some Sodium Sulfate that is 10-15 years old, it may still be
good. I have some old Metol I know has gone bad. Kind of dark brown/grey.

Thanks