a)
Interpretation:Effect of unnecessarily large volume of solvent in recrystallization process should be determined.
Concept introduction:Recrystallization is technique that is used for purification of organic compounds. This process includes dissolution of solid in specific solvent at high temperature and then crystals are made again by process of cooling. Temperature of crystals is decreased to allow impurities to remain in solution only.
b)
Interpretation:No use of fresh cold solvent to wash crystals in recrystallization process should be explained.
Concept introduction:Recrystallization is technique that is used for purification of organic compounds. This process includes dissolution of solid in specific solvent at high temperature and then crystals are made again by process of cooling. Temperature of crystals is decreased to allow impurities to remain in solution only.
c)
Interpretation:Use of fresh hot solvent to wash crystals in recrystallization process should be explained.
Concept introduction:Recrystallization is technique that is used for purification of organic compounds. This process includes dissolution of solid in specific solvent at high temperature and then crystals are made again by process of cooling. Temperature of crystals is decreased to allow impurities to remain in solution only.
d)
Interpretation:Effect of use of large quantity of decolorizing carbon should be determined.
Concept introduction:Recrystallization is technique that is used for purification of organic compounds. This process includes dissolution of solid in specific solvent at high temperature and then crystals are made again by process of cooling. Temperature of crystals is decreased to allow impurities to remain in solution only.
e)
Interpretation: Effect of formation of crystals by solidified mass of oil separated from hot solution should be determined.
Concept introduction: Recrystallization is technique that is used for purification of organic compounds. This process includes dissolution of solid in specific solvent at high temperature and then crystals are made again by process of cooling. Temperature of crystals is decreased to allow impurities to remain in solution only.
f)
Interpretation: Effect of acceleration of crystallization by immediate placement of flask of hot solution in ice-water bath should be determined.
Concept introduction: Recrystallization is technique that is used for purification of organic compounds. This process includes dissolution of solid in specific solvent at high temperature and then crystals are made again by process of cooling. Temperature of crystals is decreased to allow impurities to remain in solution only.
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OWLv2 with LabSkills for Gilbert/Martin's Experimental Organic Chemistry: A Miniscale & Microscale Approach, 6th Edition, [Instant Access], 4 terms (24 months)
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- EBK A SMALL SCALE APPROACH TO ORGANIC LChemistryISBN:9781305446021Author:LampmanPublisher:CENGAGE LEARNING - CONSIGNMENT