Water samples often contain dissolved ions such as
The presence of these ions can often be detected by adding a precipitation agent –a substance that causes one of the dissolved ions to precipitate. For example, if sodium chloride is added to a water sample containing dissolved
a. Water Sample A may contain
Use the tabulated date to determine the ions present in Sample A.
Substance Added to Water Sample A | Observation |
Nacl | No precipitate forms |
|
Precipitate forms |
|
Precipitate forms |
precipitate form previous step) |
b. Water Sample B many contain
Use the tabulated date to determine the ions present in Sample B.
Substance Added to Water Sample B | Observation |
KCl | Precipitate forms |
|
No precipitate forms |
|
Precipitate forms |
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INTRODUCTORY CHEMISTRY-W/SEL.SOLN.MAN.
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