Chapter 2 Notes | Chemistry 1st Year
“Experimental Techniques in Chemistry”
- Solvent Extraction
- Paper Chromatography
See Also: 1st Year Paper Scheme 2021
See Also: 2nd Year Paper Scheme 2021
- A complete characterization of a compound must include both qualitative and quantitative analyses.
- A complete quantitative analysis of a compound generally involves four major steps.
- The process of filtration is used to separate insoluble particles from liquids and it can be performed with several types of filter media.
- If the process of filtration is used with the filter paper is to run smoothly, the stem of the funnel should remain continuously full of liquid as long as there is liquid in the conical portion.
- The filtering operation with the filter paper could be very time consuming if it were not aided by a gentle suction as liquid passes through the stem.
- The rate of filtration can be considerably increased using fluted filter paper.
- A solid compound is purified by crystallization from a suitable solvent. A solvent for crystallization should be able to dissolve the solute at high temperature and the maximum amount of the solute should be thrown out by the solvent when the solution is cooled.
- The process of sublimation involves converting a solid directly into vaporous and these vapors are then condensed to form solid again.
- Solvent extraction technique involves the separation of a solute from a solution by shaking it with an immiscible solvent in which the solute is more soluble.
- Repeated extractions using small portions of solvent are more efficient than using a single extraction but large volume of solvent.