This experiment deals with separating substances. The objective was to become familiar with the methods of separating substances from one another using decantation, extraction, sublimation techniques. Brief Introduction
This experiment was set to teach research students different methods of separating substances from one another. Materials that are not uniform in composition are set to be impure or heterogeneous and are called mixtures. The separation of the components of mixtures is based upon the fact that each component has different physical properties. The components of mixtures are always pure substances, either compounds or elements, and each pure substance possesses a unique set of properties. Every crystal of a pure substance melts at a specific temperature, and at a given pressure, every pure substance boils at a specific temperature. In this experiment the research student will use four methods of separation depending on differences in physical properties. These methods include: 1) decantation- involves the separation of a liquid from insoluble solid sediment by carefully pouring the liquid without disturbing the solid 2)Filtration- involves separating a liquid from a solid using a porous material 3) Extraction- involves using a solvent that selectively dissolves only a single component while the other components remain insoluble 4)Sublimation- involves the heating of a solid that passes directly into a gaseous phase without transitioning into a liquid phase.
Brief Procedure and Any Modifications
Weigh an empty evaporating dish to the nearest 0.001 g using a triple beam balance. Obtain 2-3 g of unknown substance from the instructor. Set up an improvised fume hood consisting of an aspirator, cork, test tubing, and funnel to capture the NH4Cl fumes during the sublimation process. Place the unknown substance in the evaporating dish, and then weigh it. Place the evaporating dish on wire gauze on the iron ring stand. Light the Bunsen...
References: if any)
Yes, the ability of the mixture of NH4Cl, NaCl, and SiO2 to be separated into different substances by physical means supports the stated purpose and proves that mixtures can be separated into their components by physical means.
Please join StudyMode to read the full document