BIOLOGY
CLASSIFICATION OF VITAMINS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Exact boiling temperature
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Temperature above the boiling point
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Temperature below its boiling point
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None of the above
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Detailed explanation-1: -A vacuum distillation is used when the boiling point of the compound (or the solvent) is too high (Tb>150 oC) in order to distill the compound (or the solvent off) without significant decomposition.
Detailed explanation-2: -For best results, a vacuum distillation should be carried out at a pressure where your compound boils between 45 oC and 180 oC. 0.1 mmHg is appropriate for many organic compounds.
Detailed explanation-3: -Boiling commences when the vapor pressure of a liquid or solution equals the external or applied pressure (often the atmospheric pressure). Thus, if the applied pressure is reduced, the boiling point of the liquid decreases.
Detailed explanation-4: -At ambient pressure at room conditions the boiling point of water is arpund 100 degrees celsius but when we boil the water in vacuum conditions, it takes only 15 degrees celsius of temperature to boil the water This drop in boiling point is the direct result of reduction in the ambient pressure.