Reference no: EM132590866

One common way to determine Phosphorous in urine is to treat the sample after removing the protein, with molybdenum (VI) and then reduce the 12-molybdophosphate with ascorbic acid to give an intense blue color species called molybdenum blue. The Absorbance of molybdenum blue can be measured at 650 nm. 

A patient produced 1122 mL of urine in 24 hours. A 1.00 mL aliquot of the sample was treated with Mo(VI) and ascorbic acid and diluted to a volume of 50.00 mL. A calibration plot was prepared by treating 1.00 mL aliquots of Phosphate standard solutions in the same manner as the urine sample. The absorbances of the standards and the urine sample were obtained at 650 nm, and the following results were obtained:

Solution??absorbace at 650 nm

1.00 ppm P??0.230

2.00 ppm P??0.430

3.00 ppm P??0.630

4.00 ppm P??0.840

Urine sample??0.518

(i) Construct a plot of the calibration curve and find the slope, intercept and the number of ppm of P in the sample.

(ii) What mass in grams of phosphorous was eliminated per day by the patient?

(ii) What is the phosphate concentration in the urine in mM?