Determination of soil organic matter by loss on ignition

Method 5.7a. Determination of soil organic matter by loss on ignition 

Method 5.7b. Determination of easiiy oxidizabie organic C by Tinsiey s wet combustion 

Safety. The addition of concentrated sulphuric acid on sodium (or potassium) dichromate is to produce chromium trioxide, which is a powerful oxidizing agent capable of oxidizing carbon to carbon dioxide. The solution is loosely called chromic acid, but although true chromic acid H CrO has not been isolated, the aqueous solution contains dichromic acid, The 

Reaction equations. Oxidation step dichromate (Crfi/-) and organic carbon (C°)  

Titration step ferrous ion (Fe +) with excess dichromate  

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