A DETERMINATION OF IRON BY FLAME AAS

1 The sample is nebulised into an air-acetylene flame, where it is vaporised iron compounds are atomised and the iron atoms thus formed absorb radiation from a hollow-cathode lamp. The absorbance is measured at a wavelength of 248.3 nm. 

1 This procedure yields a standard curve, which is iinear up to approximateiy 5 mg/L 

2 The detection limit is approximately 0.05 mg/L in the digest. The determination limit is approximately 0.15 mg/L (7.5-18 mg/kg in the dried plant material). 

1 The reproducibility of determinations by this procedure should give, at reasonable control and thorough sample preparation, a coefficient of variation within 5 % + 5 mg/kg. 

1 B Stock Solution. Fe concentration 1000 mq/L - Dissolve 7.0170 g of ammonium iron 

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