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is the branch of chemistry principally concerned with determining the chemical composition of materials, which may be solids, liquids, gases, pure elements, compounds, or complex mixtures. In addition, chemical analysis can characterize materials but determining ....

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.... when a known one is found with identical properties. If none is found, the uknown substance must be a newly identified chemical. Tests should not use up excessive amounts of a material to be identified. Most chemical methods of qualitative analysis require a very small amount of the sample. Advance instrumental techniques often use less than one millionth of a gram. An example of this is mass spectrometry. Quantitative chemical analysis is used to determine the amounts of constituents. Most work in analytical chemistry is quantitative. It is also the most difficult. In principle the analysis is simple. One measures the amount of sam ....