Qualitative Analysis
Qualitative analysis is used in the determination of the identity of a substance. It is different from quantitative analysis, which deals with the determination of the amount of a substance. In this experiment, qualitative analysis techniques are used to determine whether or not a sample contains a certain ion. When using this method, an unknown and a reactant are mixed. The result of the reaction leads to a conclusion about the presence or absence of certain ions in the unknown. Many ions react in similar ways, and although the addition of one reagent to an unknown may not identify the ion, it limits the possibilities as to what the ion could be. A sequence of reactions used to analyze a sample is called a scheme, and it usually requires a large number of reagents and separation steps.For this experiment, the unknown may contain anywhere from 2 to all of the following cations and anions: The following reagents are used to identify the ions: .1M Ba(NO3)2 (labeled as .1M Ba2+)
Ag3(PO4) + H2SO4 a Ag2(SO4) + H3PO4 Next, the unknown had to be tested for anions. The anion flow chart was followed. 2 drops of unknown were reacted with Ba2+, and there was no reaction. 2 more drops of unknown were reacted with Ag+, and white and tan precipitates formed. H2SO4 was added to the test tube containing the precipitates, and a white precipitate was left. This confirmed that PO43- was present but dissolved when the H2SO4 was added (as was found in part 1 of the experiment), leaving the Cl-. Therefore, the anions present were Cl- and PO43-.
Some common words found in the essay are:
Cu2+ Cr3+, Cl- PO43-, Ba2+ Ag+, Ag+ HCl, Introduction Qualitative, H2SO4 Ag2SO4, PO43- Cu2+, Cu2+ NH4+, PO43- Ag+, NH4OH NaOH, flow chart, precipitate formed, 2 drops, cl- po43-, flow charts, ions unknown, test tube, h2so4 added, qualitative analysis, unknown ions, ions left unreacted, 2 drops reagent, flow chart incorrect, 2 drops unknown, result incorrect flow,
Approximate Word count = 2133
Approximate Pages = 9 (250 words per page double spaced)
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