I wrote chemetrics as suggested and asked the following questions:
1) Is it normal for liquid to appear at the titret tip after snapping
the score?
2) Is it normal for liquid from the titret to enter the wine sample?
3) Will the results be accurate (in this case 15 mg/l was indicated).

Here is Chemetrics Response:

<<It is not unusual for a drop or two of the valve assembly's content to be
lost
when the valve assembly is attached to the ampoule, or when the ampoule is
snapped at the score mark. This is not a problem if only a drop of the
assembly's contents is dispensed into the sample prior to its introduction
into
the test ampoule. However, the majority of the assembly's content should
enter
the test ampoule, so if all or most of the assembly's content enters the
sample
prior to beginning testing or is otherwise lost ,this is a problem.

As long as the user sees the blue color in the test ampoule, all is well.

I hope this helps. Please let me know if you have additional questions.

Regards,


Technical Services
Chemetrics, Inc.
ph: 540-788-9026
fax: 540-788-4856
>>>>>>

S
o I guess its not unusual for liquid to leak.

KB


--

"K. B." > wrote in message
...
> Thank you, I did write using the link you provided and will post the
reply!
>
> KB
> Saint Charles County, Missouri
>
>
> "Ed Marks" > wrote in message
> ...
> > I have no idea - but your observation made me go back and look at the
> titret
> > information sheet. I really hadn't paid attention to whether there was
> > anything in the valve assemble that you put onto the ampule, and found
out
> > there is. Supposedly it has approximately .05 ml of phosphoric acid -
> which
> > I can see in the harder plastic tube ahead of the valve. I assume this
> > needs to get into the ampule when you press on the valve, to acidify the
> > wine sample that goes into the ampule and release the SO2 to react with
> the
> > reagents in the ampule. If, for some reason, the phosphoric acid is
going
> > out of the valve assembly rather than into the ampule, you are probably
> not
> > getting an accurate test result - unless Chemetrics assumes a small
amount
> > will come out and it doesn't matter. That's my interpretation at
least -
> > why don't you send an e-mail to Chemetrics
> > (http://www.chemetrics.com/contact.html and select "Technical
Questions")
> > and see what they say. If you do that, please share what you hear from
> > them.
> >
> > Ed
> >
> >
> >
> > "K. B." > wrote in message
> > ...
> > >
> > >
> > > "Ed Marks" > wrote in message
> > > ...
> > > > Nothing should come out of the tip into the wine sample. Did you
> slide
> > > the
> > > > rubber tube with the valve all the way onto the ampule (to the white
> > line)
> > > > before snapping the end of the ampule? Yes there's a starch
solution
> in
> > > the
> > > > ampule, but it shouldn't come out due to the vacuum in the ampule.
> > > >
> > > > Ed
> > > >
> > >
> > >
> > > I slid the tube all the way over the ampule and then snapped. When I
> > placed
> > > the tube in the sample, before squeezing the tube, you could see the
> > mixing
> > > of the contents of the tube with the sample. However, the ampule
turned
> > > almost black, and stayed that way until about the 10 marking on the
> ampule
> > > (it then started to fade). At 15 it was almost back to the original
> color
> > of
> > > the sample. Something did definitely come out of the end into the
> sample.
> > > Is the test still valid?
> > >
> > > KB
> > >
> > >
> >
> >
>
>