posted by anne .
In the following test for Sulfated Ash, ammonium carbonate solution was added. What is the purpose of adding ammonium carbonate solution?
Heat a silica crucible to redness for 30 minutes, allow to cool in a desiccator and weigh. Place 1g of the substance in the crucible and add 2ml of 1mol/L Sulphuric Acid. Heat, first on a water bath, then cautiously over a flame,then progressively to about 600°C. Continue the incineration until all black particles have disappeared and then allow the crucible to cool. Add a few drops of 1mol/L Sulphuric Acid, heat and incinerate as before and allow to cool. Add a few drops of Ammonium Carbonate solution (15.8g in 100ml).Evaporate and incinerate carefully,allow to cool, weigh and repeat the ignition for 15 minutes to constant weight.