[alt-photo] Re: Stoichiometry for the nonscientist

etienne garbaux photographeur at nerdshack.com
Mon Aug 2 15:34:45 GMT 2010

David wrote:

>It seems this hole is much deeper than what was represented
>originally.  I can see why prepackaged kits are so popular.
>You went from gms to ml?

To get the right amounts of the reactants, you necessarily must mess 
with the molecular weights of the compounds involved.  You can do 
this every time you have a reaction to conduct, or you can do it 
beforehand by making up solutions that are based not on absolute 
weight but rather on molecular weight.  That's all.  If you follow 
along, I believe the previous e-mail explained clearly how to get 
from grams to ml.

And yes, mixing from a kit is easier than calculating reactions, and 
you don't have to worry about fizzing (or worse) from evolved gasses 
or the need for ice baths to keep temperatures from running 
away.  With potassium oxalate, you don't even need a kit -- just buy 
potassium oxalate (preferably, from a reputable scientific supplier 
like Malinckrodt Baker, so you know exactly what you have).

Best regards,


More information about the Alt-photo-process-list mailing list