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Cards In This Set
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WHAT ARE THE CONDITIONS REQUIRED FOR DISTILLATION TO BE ACCOMPLISHED?
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- At least one component in the mixture must be volatile.
- If two or more volatile liquids are present, they must differ by a boiling point of at least 50. - The components must not form an azeotrope. |
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GIVE A SUMMARY OF SIMPLE DISTILLATION OF TWO LIQUIDS.
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The boiling point of the mixed solution will be between the boiling points of the two pure compounds.
As one of the compounds is removed, an increase in boiling point will occur due to enrichment of the other compound. There is never a 100% seperation between the compounds, only an enrichment. |
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WHAT IS FRACTIONAL DISTILLATION?
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Occurs when the compound with X1 composition is not yet collected and is allowed to re-equilibrate at temperature T2, it will have a new composition (X2) with more enrichment in one of the compounds (A).
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WHAT IS ALLOWS FOR FRACTIONAL DISTILLATION TO OCCUR IN A FRACTIONATING COLUMN?
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Round glass beads which provide a large surface area for the gases to cool.
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WHAT IS THE CRITERIA OF PURITY FOR A LIQUID IN THIS LAB?
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- Boiling point of the purified liquid.
- Refractive Index (R.I) of th e liquid. |
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WHAT IS REFRACTIVE INDEX?
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Measure of change of light path from one medium (air) to another (liquid).
How much the light bends depends on how much is dissolved in the liquid. (concentration of atoms and arrangement within the molecule). |
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WHAT IS RI DEPENDANT ON?
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R.I is dependent on the wavelength of the light and the temperature.
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WHAT IS THE EQUATION FOR THE CORRECTIVE RI?
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NT1=nobs + (0.00045)*(Tobs-T1)
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WHAT IS THE MAXIMUM AMOUNT OF LIQUID THAT SHOULD FILL AN RB FLASK?
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2/3 full
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WHAT SHOULD THE THERMOMETER BE LUBRICATED WITH AND WHAT IS IT INSERTED INTO?
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Glycerol
Stillhead adapter |
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WHAT IS THE PURPOSE OF ALUMINUM FOIL?
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To get a good distillation, it should be done evenly and slowly, therefore to minimize large heat changes, aluminum foil is used to insulate the heat.
A good distillation results from attainment of equilibrium between liquid and vapour. |
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HOW DO YOU CALCULATE A THERMOMETER?
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Place the thermometer in an ice bath that covers the marked line on the thermometer for a few minutes and see if it reads 0 degrees.
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