[mdlhvn]

I've carried out phosphate determination experiments in my lab. The reagents are:

1. Amstrong reagent: Ammonia molybdate, potassium antimony tartrate and con. sulfuric acid   

2. Ascorbic acid

I knew that Ammonia molybdate and Ascorbic acid involves in the formation of "molybdenum blue" but what is the role of potassium antimony tartrate. Is it a catalyst, of any others roles?

Thank you in advance!

[chiralic]

The role of Antimony potassium tartrate is to increase the rate of reduction of ascorbic acid to form a intensely colored blue complex.

Check it out this reference:
Murphy, J. and J. P. Riley. A modified single solution method for the determination of phosphate in natural waters.  Analytica Chimica Acta,1962, 27, 30.

Happy Xmas Eve and Merry Christmas

Chiralic

[mdlhvn]

Thank you very much. I will try

Merry Christmas and Happy New Year!

[mdlhvn]

Check it out this reference:
Murphy, J. and J. P. Riley. A modified single solution method for the determination of phosphate in natural waters.  Analytica Chimica Acta,1962, 27, 30.

I can only find the abstract of this article.
I want to know the mechanism of the formation of molybdenum blue to know the whole roles of potassium antimony tartrate. Should I use it at specific ratio with molybdate reagent? and what ratio?

Thank you in advance!!!