chemical question

[glbeas]

What is the difference between the bisulfite and the metabisulfite, if any?

 

[john_s]

There is a bit about this on Ryuji Suzuki's site:

http://silvergrain.org/Photo-Tech/chemistry-misnomers.html

 

[glbeas]

Thanks! Quite interesting how that works out.

 

[dancqu]

What is the difference between the bisulfite and
the metabisulfite, if any?

Likely one difference is the temperature of crystallization; the
meta being precipitated at higher temperatures. A dehydration
takes place. A combining of two orthos into one meta minus one
H2O is the result. The metabisulfite is two bisulfites minus a H2O.
Or, 2,NaHSO3 = Na2S2O5 + H2O.

Borates do the same thing, dehydrate; ortho, meta, tetra. Of
course they also hydrate; metabisulfite, with water, will become
the bisulfite. Dan