What is the reagent responsible for the formation of H2S in the qualitative analysis of group II?
when the cations are separated into subgroups, what is the purpose of the potassium hydroxide,KOH?
I have no idea what your lab procedure is. You could be using H2S gas or you could be generating H2S in situ by using thioacetamide and heating the solution.
What do you thing the KOH does?
THanks for your help dr bob you're useless.
In the qualitative analysis of group II cations, the reagent responsible for the formation of H2S is sodium sulfide (Na2S) or ammonium sulfide [(NH4)2S]. These reagents are used to precipitate the sulfide ions of the group II cations as insoluble sulfides.
Now, when the cations are separated into subgroups, potassium hydroxide (KOH) is used for a different purpose. It serves as a precipitating reagent for the hydroxide ions of certain metal cations. KOH is added to the solution containing the group II cations to precipitate the group II hydroxides.
The purpose of adding KOH is to separate the group II cations into two subgroups based on their solubility in KOH. Some cations will form insoluble hydroxide precipitates, while others will remain soluble. This separation helps in the further identification and analysis of these cations in subsequent procedures.