Qualitative Analysis Question: How can I setup a procedure to test if a solution
ID: 1042643 • Letter: Q
Question
Qualitative Analysis Question:
How can I setup a procedure to test if a solution contains all or a few of the following: Pb2+, Bi3+, Sb3+, and Zn2+. I cant use H2S or Thioacetamide to separate the solution. Basically I have a solution that can have any amount of those 4 cations. I just need a flow chart or step by step procedure to test if each one is present in the solution. The only hint I have is I probably have to add strong bases and acids to precipitate or separate the cations. Help. Thanks.
Explanation / Answer
In intergroup seperation of cations, the first group elements (pb2+,Ag+)are precipitated as chlorides using HCl. To the centrifugate H2S is passed and group 2 elements ( Ca2+,Sr2+,Ba2+,pb2+) are precipitated as their sulphides.
As per the question, we cant use H2S. Any methods which can precipitate group elements to their hydroxides, or sulphide, carbonates etc... Can be used for the intergroup seperation of cations. Here group 2 element pb2+ ,Bi3+,Sb3+ can be precipitated as sulphates using Na2SO4(aq) and ethanol. Zinc can be precipitated as their hydoxide using excess NaOH.
The precipitate obtained are analysed in its conventional methods.