Michael Thomas Harbuck							Chem II – 2046C
30-0100-2008									Dr. Fraser

Qualitative Compound Analysis Laboratory
I.  Qualitative Analysis Lab.
II. Purpose of the laboratory experiment stands to teach the fundamental use of senses in determining the contents of solutes and or ions of particular type in these said solutions.  The specific ions are confirmed with a series of tests, and reactions, which, in a  flow chart type manner, are then used to either exclude, or prove the presence of  a particular cation.  A group of ions is used as a given, whereby the presence of these is tested.  
Group I:  Hg2 2+, Ag+, and Pb 2+
III.  Firstly, a sample of unknown is chosen from the supplied samples.  This is recorded in the laboratory experiment notebook, and in this case,  is the sample number 44.  A  hot plate should be set up, and a beaker, in which the reagent vessels can be heated, should also be constructed, and set in motion.  A small amount of the unknown is places in a RG (reagent glass), and the first of the confirmation/exclusion tests is performed.  
a.  HCl is added to the unknown, where a white precipitate forms.  Of the three  possible precipitates, one is  soluble in water, and will solve when heated, disappearing from view.  
There is a precipitate formed in this experiment, which confirms the presence of at least ONE of the group I  known cations.  
b. The precipitate is then centrifuged, and washed.
c. The decantate is tested for Lead using a solution of Potassium Chromate.  NEGATIVE for LEAD cations.
d. To the solute, in order to check for the presence of Mercury, a solution of ammonium ions is added.  There IS a reaction which occurs with this unknown, thus POSITIVE for Mercury cations.  
e. The resulting solution containing the Ammonium ions, as well as the confirmed Hg ions, is then separated by the  centrifuge.  
f. To the remaining decantate, a solution of Nitric Acid is added.  There is no reaction with this unknown, and therefore it can me determined, that there is a NEGATIVE presence for Silver ions in sample number 44.

IV. Conclusion:  The sample number 44  contained only one of the possible cations for the Group I ions given.  This being the Hg2 2+.

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