DETERMINATION OF PHOSPHORUS IN SOIL (Olsen’s Method 1954)

DETERMINATION OF PHOSPHORUS IN SOIL (Olsen’s Method 1954)

Take 2.5 gm of Soil Sample in 100 ml of Conical Flask

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Add Activate Charcoal 2 Spatula

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Add 50 ml of NaHCO3 0.5 M, Maintain 8.5 pH by HCl & NaOH

                                                                                          ↓     (Shake for 30 Minutes and Filter into

                                                                                     100 ml of Beaker through Whatma                                                                              Peper No.1 in 100 ml Beaker)

Take 5 ml Extract or Filtrate in 25 ml of Volumetric Flask

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Take 5 ml Extract or Filtrate in 25 ml of Volumetric Flask

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Add 5 ml Ammonium Molybdate, 1.5 % Solution

                                ↓(Remain Sample for 50 Minutes)

Make volume with D.W. Approx 22 ml

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Add Fresh 1.0 ml Stannous Chloride

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Make Volume up to 25 ml with DW and Take reading at 660 nm wavelength by Spectrophotometer