RE: bichromate gum
Indeed. There are two forms of NaDi: anhydrous and dihydrate. My
calculation was made according to dihydrate -> since that's what you
"usually" get from the chemical suppliers. Maybe Judy's NaDi was the
anhydrous form, therefore in her experience NaDi was faster than KDi at
the same w/v strength.
Lets re-make the calculation for anhydrous NaDi:
[KDi Strength] * ( [NaDi m.w.] / [KDi m.w] ) = [equiv. NaDi Strength]
10% * ( 262.01 / 294.19 ) = 8.9% (~ 9%)
So, 8.9-9% NaDi is virtually the same as 10% KDi (or 8.5% NH4Di)...
Thank you for the remark Alberto.
12 Temmuz 2008, Cumartesi, 8:15 am tarihinde, Alberto Novo yazmış:
> The "reply-to" of Loris' message was set to his personal address instead
> The List, so I post my reply again
>> sodium dichromate's (NaDi) molar mass is 298.02g
> this is for Na2Cr2O7.2H2O.
> For the anhydrous form, the M.W. is 262.01. In this case the math changes