The application of complexes in qualitative inorganic analysis

33 THE APPLICATION OF COMPLEXES IN QUALITATIVE INORGANIC ANALYSIS The formation of complexes has two important fields of application in inorganic qualitative analysis  

Another important application is the test for iron(III) ions with thiocyanate. In slightly acid medium a deep-red colouration is formed, owing to the stepwise formation of a number of complexes  

Some complexes are precipitates, like the bright-red precipitate formed between nickel(II) ions and dimethylglyoxime  

Masking may also be achieved by dissolving precipitates or by the selective dissolution of a precipitate from a mixture. Thus, when testing for lead in the presence of silver, we may produce a mixture of silver and lead chloride precipitates  

If ammonia is added, silver chloride dissolves in the form of the diammine-argentate ion  

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