"David C Breeden" wrote in message
...
Tom S ) wrote:
"David C Breeden" wrote in message
...
Hey,

does anyone but me find that their potassium hydrogen phthalate gets
pretty moldy pretty quickly? I've started storing it in the
fridge--how do other people store theirs?

Baking at ~250°F for an hour or so (to drive off water and kill any mold
spores) and keeping it in a tightly sealed glass bottle should stop that
problem.

Tom S
www.chateauburbank.com


No, no, sorry. I mean the *solution* gets cloudy pretty quickly,
not the powder.

KHP is not normally used in liquid form as a standard - probably at least
partially for that very reason, but mainly because the titer will shift
somewhat with age/use, thereby reducing its value as a precise standard.

Best to use the dry powder for standardizing.

Tom S
www.chateauburbank.com