Re: Dichromate of choice

Terry King (101522.2625@CompuServe.COM)
17 Jul 96 18:24:54 EDT

Judy

>> A chemist I know, who did some tests, told me that that was what he found. If
>> others have found that the sodium salt gives better results then we all have
>> reason to change. In my current catalogues the sodium salt costs twice as
much
>> as the ammonium.

>I haven't noticed, Terry, that you believe everything *I* tell you so
>trustingly. Meanwhile we know nothing about how this fella claimed to be
>a chemist (tho he obviously wasn't a gum printer) framed his "tests, or
>even if he had his glasses on. The thing we do know is that he was wrong.

He was and is the research person for the Historical Group of the RPS. I have
learned to trust his judgement. A & P work well enough for me but I am ready to
change if sodium works better. Does any body else on the list have any views
based upon practical experience ?

>But who said anything about "better"? I simply said that since sodium
>dichromate is more soluble in water, a saturated solution is *faster,* all
>other things being equal.

If it's not any better why bother ?

>I also said,
>
>> >Since the strength of dichromate is one of the factors in staining in both
>> >plain dichromate stain and pigment stain,
>
>To which you replied,
>> I have never found that there is a practical difference. In my experience I
>> have never had any difficulty with staining.
.
>I never said "problem," Terry, I simply mentioned staining.

Why ?

> But since almost
>immediately you add (see below) that you never used sodium dichromate I
>wonder why you are pressing the issue....

I did not know that there was an issue to press.


>> I have never used the sodium salt but I am not sure that it follows that it
will
>> stain more.

>Wanna bet.

Sure.If you do the tests and get them independently assessed, I'll bet you a
bagel.

Terry