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John Cahill
1-Apr-2007, 12:19
FRiends one and all,

Please help me avoid trying to fugure out the percent of acidity of an every day acetic acid stop bath? I know, I know, glacial to 28% to three to nine to whatever is easy for some, but not for this former history major.

What, about, is the acidity of the average stop bath?

TIA

Nick_3536
1-Apr-2007, 12:31
http://www.jackspcs.com/sb1.htm

Kodak SB-1

Or do you want a pH number?

John Cahill
1-Apr-2007, 12:49
http://www.jackspcs.com/sb1.htm

Kodak SB-1

Or do you want a pH number?

*****
Hi Nick,
Nope, that link was just fine. It said that a usual stop bath was 1.4% acetic acid. Just what I needed. Thanks a bunch.

Jan Pietrzak
1-Apr-2007, 12:50
John,

pH is one thing, concentration is another. Don't feel bad my chemistry class was high school and JFK/LBJ was the prez.

For film I mix half the dilution (not as stronger) and paper is a bit stronger (regular plus)

Jan Pietrzak

stompyq
1-Apr-2007, 12:58
Around pH 2-3 (exactly 2.04 if you consider that glacial acetic acid is 17M solution).

Ron Mowrey
5-Apr-2007, 07:43
Kodak Indicator Stop Bath is pH 3.0 at 68F.

As a check, I just measured it with my handy dandy pH meter.

Ron Mowrey