The Total solution for NCERT class 6-12
Why is nitric acid addedto sodium extract before adding silver nitrate for testing halogens?
While testing theLassaigne’s extract for the presence of halogens, it is first boiled withdilute nitric acid. This is done to decompose NaCN to HCN and Na2Sto H2S and to expel these gases. That is, if any nitrogen andsulphur are present in the form of NaCN and Na2S, then they areremoved. The chemical equations involved in the reaction are represented as