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Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: zengxin on September 16, 2011, 04:58:26 AM

Title: Sodium hypophosphite purity is 102%, how to explain it?
Post by: zengxin on September 16, 2011, 04:58:26 AM

Sodium hypophosphite purity is 102%, how to explain it?

Specification:
NaH2PO2.H2O    %≥102
Na2HPO3           %≤0.3
Ca                    %≤0.001
Fe                    %≤0.0002
SO4                 %≤0.01
CL                   %≤0.003
PH                     6--8
Pb                   %≤0.0001

Anyone can explain that?

Title: Re: Sodium hypophosphite purity is 102%, how to explain it?
Post by: Borek on September 16, 2011, 05:30:54 AM

Idiocy IMHO. Probably some artifact of assay method or hygroscopicity.

Title: Re: Sodium hypophosphite purity is 102%, how to explain it?
Post by: zengxin on September 18, 2011, 10:16:03 PM

You can check the Spec. of Sodium hypophosphite on alibaba, the purity is 102%. I don't know why ?

Title: Re: Sodium hypophosphite purity is 102%, how to explain it?
Post by: AWK on September 20, 2011, 04:39:06 AM

Purity is determined by a redox titration, but the reagent contains also other reductor Na2HPO3 and titration determines all reductors.

Title: Re: Sodium hypophosphite purity is 102%, how to explain it?
Post by: crosemeyer on September 23, 2011, 05:50:25 PM

Couldn't this simply be due to w/v% being used?

Like 102g hypophosphite in 100mL water would be 102%w/v.