post retracted for lack of response

I've read that the HT-2 test, a silver for sulfur test, has
a two month life span. My HT-2 came from P. Formulary
and they may have been the source of information.

Silver nitrate and acetic acid make up the HT-2 test. I
don't know why it should go bad; if it does. I've asked the
same question of this group and gotten no response.

Apparently the reactions involved are more complex
then would first seem to be the case. One thing I think
for certain; the sulfide of silver is produced if there be any
sulfur present. From reading of the test, the acid is present
to free sulfur from any remaining thiosulfate. But nitrate
is a very strong oxidizer and so why sulfur rather than
a sulfate being freed? For that matter why a sulfide
of silver and not a sulfate.

At any rate I'm not going to buy any more HT-2 or compound it
until I find out why it should go bad. I think the HT-1a test,
properly done, will do just as well. Dan

post retracted for lack of response
I didn't realize that there was a deadline for an answer? If so, it would be interesting to note.

I've read that the HT-2 test, a silver for sulfur test, has
a two month life span. My HT-2 came from P. Formulary
and they may have been the source of information.

Silver nitrate and acetic acid make up the HT-2 test. I
don't know why it should go bad; if it does. I've asked the
same question of this group and gotten no response.

Apparently the reactions involved are more complex
then would first seem to be the case. One thing I think
for certain; the sulfide of silver is produced if there be any
sulfur present. From reading of the test, the acid is present
to free sulfur from any remaining thiosulfate. But nitrate
is a very strong oxidizer and so why sulfur rather than
a sulfate being freed? For that matter why a sulfide
of silver and not a sulfate.

At any rate I'm not going to buy any more HT-2 or compound it
until I find out why it should go bad. I think the HT-1a test,
properly done, will do just as well. Dan

Dan,
Kind thanks for this answer. You're right . . it seems strange that this solution should keep so poorly. I'm no chemist, so your clear explanation is helpful.
To further prove how much I'm not a chemist, here's another —perhaps, näive question —which your response brings to mind: you say that nitrate is a strong oxidier. Does that mean it can, in itself, become easily oxided? Just wondering.

I didn't realize that there was a deadline for an answer? If so, it would be interesting to note.

lol... Hortense, not at all. To be honest, I had become a little embarassed by the question I posted. I simply thought that one reason for receiving no responses might have been that the question was considered a little dumb, that's all.

There. Now you have my raw ego before you, nerves, veins and all.. Keep the stop bath away!

Happy holidays!

Dan, you say that nitrate is a strong oxidizer.
Does that mean it can, in itself, become easily
oxided? Just wondering.

Just the opposite. Nitrates supply oxygen.
Nitrates will oxidize many substances. As a
youngster I used saltpeter, sodium nitrate,
to make rocket powder. Dan

Just the opposite. Nitrates supply oxygen.
Nitrates will oxidize many substances. As a
youngster I used saltpeter, sodium nitrate,
to make rocket powder. Dan

Saltpeter? Isn't that the stuff which is supposed to reduce the effect of your libido? Pretty multi-purpose then: on one hand it can suppress a "rocket", on the other hand, it makes one take-off!

(sorry for the end-of-year humor in questionable taste, and thanks for another good clarification!)