The amount of nitrogen can be determined from organic matter?
if yes, then give the formula?
There is a general relationship that the organic C/N ratio in soil is in the range 10 to 20 of C to 1 N. However one could not say this was a 'determination'.
You may only get an idea from C/N ratio but there is no good relationship where convincedly you may calculate the N content from organic matter content. Moreover, it varies from soil types and many other factors.
Dear Suneel Ji,
Yes, the amount of nitrogen in organic matter can be determined using the Kjeldahl method. The Kjeldahl method is a widely used technique for the determination of nitrogen content in organic and inorganic substances, especially in organic matter such as soil, plant material, and food.
The basic steps of the Kjeldahl method include:
Digestion: The organic material is digested with concentrated sulfuric acid. During this process, nitrogen present in the organic matter is converted into ammonium sulfate.
Distillation: The ammonium sulfate formed in the digestion step is then distilled with a strong base (usually sodium hydroxide). This results in the release of ammonia gas.
Titration: The liberated ammonia gas is captured in a known volume of standard acid solution. The excess acid is then titrated with a standard base solution to determine the amount of acid consumed. This information is used to calculate the nitrogen content in the original sample.
The formula to calculate the nitrogen content is:
Nitrogen %=(Volume of acid used in titration×Normality of acid×Equivalent weight of nitrogenWeight of the sample)×100Nitrogen %=(Weight of the sampleVolume of acid used in titration×Normality of acid×Equivalent weight of nitrogen)×100
The equivalent weight of nitrogen is 14 (since nitrogen is diatomic, with a molecular weight of 28 g/mol, and the Kjeldahl method measures N, not N2).
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