In water nitrogen is present in different forms namely Nitrate, Nitrite Ammonia & organic Nitrogen. All these forms are biochemically interconvertible and are component of nitrogen cycle. In water ammonia is present in surface water. Its concentration is generally low in ground water because it is absorbed in soil particles and clays and is not leached readily form soils.

Material and Apparatus:

·         Spectrophotometer

·         Sample cells

·         Distilled water

·         Ammonia Salicylate Powder Pillow

·         Ammonia Cyanurate Reagent Powder Pillow

Procedures:

·         Turn on spectrophotometer

·         Select the test

·         Prepared Sample: Fill a sample cell to the 10-mL mark with sample.

·         Blank Preparation: Fill a second sample cell to the 10-mL mark with deionized water.

·         Add the contents of one Ammonia Salicylate Powder Pillow to each cell.

·         Insert the stopper or cap the cell and shake to dissolve.

·         Start the instrument timer. A three-minute reaction period will begin.

·         When the timer expires, add the contents of one Ammonia Cyanurate Reagent Powder Pillow to each cell.

·         Stopper or cap and shake to dissolve.

·         Start the instrument timer. A 15-minute reaction period will begin. A green color will develop if ammonia-nitrogen is present.

·         When the timer expires, wipe the blank and insert it into the cell holder

·         ZERO the instrument. The display will show: 0.00 mg/L NH₃–N.

·         Wipe the sample and insert it into the cell holder. READ the results in mg/L NH₃–N.

References

1. Sadhana C.; Ananda Dev G.; Handbook of Water, Air and Soil Analysis; a Lab Manual; International-E-Publication;2014

2.Frank R.Spellman; Handbook of water and wastewater treatment plant operations; Lewis publishers;2003.

3.Leena Deshpande;Water Quality Analysis Laboratory methods; New Delhi; India.