Note 37 — Chapter IX · COMPOUNDS OF CARBON WITH OXYGEN AND NITROGEN

Calcium chloride enters into double decomposition with ammonium carbamate. Acids (for instance, sulphuric) take up ammonia, and set free carbonic anhydride; whilst alkalis (such as potash) take up carbonic anhydride and set free ammonia, and therefore, in this case for removing water only sodium or potassium carbonate can be taken. An aqueous solution of ammonium carbamate does not entirely precipitate a solution of CaCl2, probably because calcium carbamate is soluble in water, and all the (NH3)2CO2 is not converted by dissolving into the normal salt, (NH4O)2CO3.