Ammonia

Ammonia NH₃  =  17.03

For 18m and 13.5m ammonia use analytical reagent grade solutions of commerce containing 35% and 25% w/w of NH₃ and weighing 0.88  g and 0.91  g per  ml, respectively.

Solutions of molarity x m should be prepared by diluting 75x  ml of 13.5m ammonia or 56x  ml of 18m ammonia to 1000  ml with water.

When ammonia is specified and the strength is not stated, use a reagent prepared by diluting 67  g of 13.5m ammonia to 100  ml with water. When used in the limit test for iron, it complies with the following test.

Iron Evaporate 5  ml of the reagent being examined to dryness on a water bath, add 10  ml of water, 2  ml of a 20% w/v solution of citric acid and 0.1  ml of thioglycollic acid . Add sufficient of the reagent to make the solution alkaline and dilute to 20  ml with water. No pink colour is produced.