Author: VF Date: 01/09/2011 3. Transfer to a volumetric flask of IL and add 42 ml of sodium hipoclorite 10% and adjust volume with distilled water up to IL 4 Transfer the solution to the dark glass botde and keep it in the fridge. Do not use this solution 30 d after its preparation Preparation of standards repare 10% formic acid EBA solution(FAtEBA 10% in a volumetric flask of 500 ml add 45 ml of formic acid, 5 ml of EBA and adjust the volume to 500 ml with the volumetric flask, then add distilled water(first bring about 400 ml of H2o formic acid& then adjust to 500 ml with H2O) the 7 solutions of ammonium chlonde in GA EBA as described in the following table ST1 is prepared in a volumetric flask of250 ml are prepared in volumetric flasks of 20 ml. Concentration Concentration Preparation(mg NH/L) (mg NELCIL) 200 628.30 ST1 T 157 i mg NHACI in 250 ml of(FATEBA 10%) ST 2 10 ml of ST1+10 ml(FA+EBA 10%) ST3 S mil of STIR 15 ml(FA EBA 10%) 62.80 2 ml of ST 18 ml(FA EBA 10% STA 31.40 STS l ml of STI t 19 ml(FA EBA 10%n 15.71 ST6 0.5 ml of STI 19.5 m A EBA 10%) ST7 0.1 ml of STI 19.9 ml(EA-EBA 10% Procedure Preparation of the standard series tubes in duplicate where to each tube 100 ul of each standard solution l Preparc 7 prepared previously is introduced and 4.5 ml of solution B 2 Add to each tube 4.5 ml of solution A t 45 3 Prepare another tube(blank) where 100 ul of FA+EBA 10% solution is added ml of solution A 4.5 ml of solution B 4. Leave at ambient temperature for about 4h Read the absorbance at 625 nm. Take the centrifuged samples acidified with(FA-EBA 10%) according to the Determination procedure for RUMEN VFA EBA analysis test tube of 10 2. Centrifuge samples at 1700 g for 20 min into a 3. Analyze each sample in duplicate Take 100 ul of the supernatant 4. Add 4.5 ml of solution A d immediately after 4 5 ml of solution B 5. Close the tubes and vortex about 4h that of STI. 6, e at erature for sample is higher than when the absorbance at 625 nm If the reading of a solution. repeat the analysis by diluting the with FA EBA 10% account calculating the concentration, the diluuon will have to be taken into