1) Most convenient technique to separate and recover water and magnesium sulfate (a salt) from an aqueous solution of magnesium sulfate a) Simple distillation because salts usually have higher boiling points than water b) Filtration because the salt is in the liquid c) Evaporation because water is not needed 2) Technique used to separate crystals of calcium chloride from an aqueous solution of calcium chloride a) Crystallization b) Fractional distillation c) Filtration 3) __________________ is a technique used for the purification of substances. A separation technique to separate crystalline solids from a saturated solution. a) Distillation b) Evaporation c) Crystallization 4) The change of state from gas to liquid in a simple distillation happens at the a) distillation flask b) condenser c) collecting flask 5) When the substances in a liquid mixture have very close boiling points, the most convenient technique of separation is a) fractional distillation b) simple distillation c) chromatography 6) The separation of mixtures is a a) physical process, because nothing new is produced b) chemical process, because new substances are separated c) physical process, because it involve chemical procedures to decompose mixtures. 7) A filtration involves a) A residue, a filter paper, a funnel, a flask, a filtrate b) A flask, a condenser, a filter paper, a filtrate c) A flask, a bunsen burner, a flask, a filtrate and residue, a condenser 8) The setup corresponds to a a) chromatography b) fractional distillation c) simple distillation 9) The retention factor (Rf) is used to compare and help identify compounds in chromatography. The Rf value of a compound is equal to a) the distance traveled by the compound divided by the distance traveled by the solvent front from the base line b) the distance traveled by the solvent from the edge of the paper divided by the distance traveled by the spot from the base line c) addition of the distance traveled by both the solvent and solvent from the base line 10) In chromatography sometimes compounds do not have a visible color but they are separated, when this happens a) the substance is not identified b) the solvent must be changed to make it visible, c) a developer or locating agent is used to show the substances 11) Rf Values. The approximate Rf of Analyte B is a) 0.3 b) 0.5 c) 0.9 12) A mixture of three alcohols X, Y and Z with boiling points 60 oC, 80 oC and 92 oC respectively, is separated by simple distillation. Which alcohol is obtained first a) Z because it has a higher boling point b) Y because its boiling point in in-between c) X because is has a lower boiling point 13) A mixture of three alcohols X, Y and Z with boiling points 60 oC, 80 oC and 92 oC respectively, is distilled in an oil bath in which the oil has a B.P of 85 oC. What is correct about this? a) All alcohols will be separated. b) Only the alcohols with the lower boiling point gets to be separated c) Only alcohols X and Y are separated because their b.p. is below the b.p. of the oil bath. 14) Mixtures like sand and water can be separated by _________________ because ___________________ a) filtration - they are not soluble (heterogeneous) b) distillation - they dissolve and have different boiling points c) evaporation - they are dissolved and water has a boiling point lower than sand 15) If you are to separate a mixture of salt and water without the need to recover water, what technique would you use? a) filtration b) evaporation c) chromatography 16) A heteregeneous mixtures of a solid and liquid can be conveniently separated by a) filtration b) fractional distillation c) chromatography 17) The components of chlorophyll ( a green pigment in plants) can be conveniently separated by a) chromatography b) distillation c) filtration 18) The most striking difference between simple and fractional distillation is the presence of a a) fractionating colum b) condenser c) distillation flask 19) Water gets in and gets out in the ____________________ because______________ a) condenser, it has to be cold to turn the vapor into a liquid b) distillation flask - it maximizes the separation of water from the flask. c) collecting flask - it is mixed with the water vapor from the flask and lowers its temperature. 20) It is correct to say that in chromatography, the substance that travels the furthest with the solvent, it's a) the least soluble in the mixture b) the most soluble in the solvent c) the one that dissolves the least in the solvent

Separation techniques

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