Question

Q11 :	The phenomenon involved in crystallization techniques is
A.	None of the above	B.	Both of the above
C.	Parallel displacement of faces	D.	Antiparallel displacement of faces
Q12 :	Which method is usually used to separate coloured substances from each other?
A.	Evaporation	B.	Chromatography
C.	Simple distillation	D.	Centrifugation
Q13 :	How a mixture of isopropyl alcohol and water is be separated?
A.	Two step crystallization	B.	Two step distillation
C.	Separating funnel	D.	One step distillation
Q14 :	In solvent extraction techniquie (liquid-liquid extraction), what is the use of ether layer?
A.	To separate fibers	B.	To separate solvent
C.	To separate inorganic impurities	D.	To separate organic impurities
Q15 :	Which of the following does not influence filtration?
A.	Temperature	B.	Density
C.	pH	D.	Viscosity
Q16 :	Fractional distillation cannot be used to:
A.	Refine crude oil	B.	Separate the components of liquid air
C.	Test purity of a substance	D.	Separate methanol and water
Q17 :	When does the sublimation take place?
A.	When sufficient heat is applied	B.	The partial pressure of solute in gas phase is more than solid vapor pressure
C.	When sufficient pressure is applied	D.	The vapor pressure is equal to partial pressure
Q18 :	Which of the following separation techniques is dependent on difference in volatility?
A.	Magnetic separation	B.	Fractional crystallization
C.	Distillation	D.	Crystallization
Q19 :	Distillation can be used to separate:
A.	A liquid from a solution	B.	A solid from a solid
C.	A soluble solid from a solution	D.	An insoluble solid from a solution
Q20 :	Crystallization exploits difference in which factors?
A.	Specific heat	B.	Melting point
C.	Boiling point	D.	Bubble point
Q21 :	Which one of the following is a disadvantage of evaporation?
A.	The solvent is not recovered	B.	It cannot be used for insoluble solids
C.	It always requires heat.	D.	All of the solute is recovered

Answer 1

11.(C) Parallel displacement of faces involved in crystallization techniques.

12.(C) Simple distillation is used to separate coloured substance from each other.

13.A two-step distillation is employed where there is an addition of benzene which is soluble in IPA and thus forms a layer. Now IPA and benzene mixture can be separated from water using a separating funnel. Further distilling, we get benzene and IPA.

14.(C) Since ether is a non-polar compound, its layer is used to separate organic impurities.

15.(C) pH does not influence temperature