1.Define the following terms:
a. Decantation - A process for the separation of mixtures, by removing a layer of liquid, generally one from which a precipitate has settled. The purpose may be either to produce a clean decant, or to remove undesired liquid from the precipitate (or other layers). b. Contamination - The presence of particles, chemicals, and other undesirable substances, such as on or in a process tool, in a process liquid, or in a cleanroom environment c. Centrifugation - Centrifugation is a process which involves the application of the centrifugal force for the sedimentation of mixtures with a centrifuge, and is often used to separate a supernatant from a precipitate. d. Supernatant – This term denotes the liquid lying above a solid residue after precipitation, centrifugation, or other process. e. Precipitate - The insoluble product that forms in a solution after mixing substances together. 2.What reagent(s) can be used to identify and confirm Ag+, Hg22+and Pb2+ions? 3.List all the solid precipitates and their colors: 4.What is the precipitating reagent for silver ion in step 1? Would a solution of NaCl work as well? 5.What color is was the unknown? Could you make an educated guess as to any cations in your unknown from the color of the unknown?
- Spring '10
- Chemistry, Ion, drops, precipitate