Chemistry · Science General

Separation Techniques

842 Questions

Separation techniques involve physical methods to isolate mixtures, including distillation, filtration, and crystallization. Competitive exams frequently test these foundational concepts. Review the exact processes to enhance problem solving speed.

Distillation and evaporationCrystallization processFiltration methodsSeparating dissolved solidsChromatography and mass techniques

Separation Techniques Questions

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

Mixture of sand and camphor is purified by:

  1. seperating funnel

  2. distillation

  3. cooling

  4. sublimation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Sublimation is used for separating substances with on heating change directly into vapour. The vapour by cooling gives the pure substance in & solid form which is called sublimate. Here camphor wil sublime leaving behind the sand.

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

Camphor is seperated from NaCl by the method :

  1. Sublimation

  2. Distillation

  3. Sedimentation

  4. Evaporation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Camphor is separated from NaCl by Sublimation.
On heating, camphor is collected on the inner surface of the inverted funnel while NaCl left in the dish.
Note: Sublimation is the process of heating a solid to obtain vapours.
When a mixture of NaCl and camphor is heated, camphor sublimes and its vapours are obtained.
The vapours on cooling (when they come into contact with the inner surface of the inverted funnel ) condense into solid.

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

The process used for the seperation of those solids which sublime on heating from non volatile solids is :

  1. Evaporation

  2. Distillation

  3. Filteration

  4. Sublimation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The process used for the separation of those solids which sublime on heating from non volatile solids is  sublimation.

Note:
Camphor is separated from NaCl by Sublimation.
 On heating, camphor is collected on the inner surface of the inverted funnel while NaCl left in the dish.
 Sublimation is the process of heating a solid to obtain vapours.
When a mixture of NaCl and camphor is heated, camphor sublimes and its vapours are obtained.
The vapours on cooling (when they come into contact with the inner surface of the inverted funnel ) condense into solid.

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

Iodine-salt mixture can be separated through:

  1. simple distillation

  2. simple filtration

  3. sublimation

  4. fractional distillation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Iodine-salt mixture can be separated through sublimation. Iodine will sublime whereas salt will be left behind. Sublimation is a technique that helps chemists to purify. During sublimation, upon heating, a solid substance is converted to the gas phase without passing through the liquid phase.  A solid is heated under vacuum. The solid volatilizes and condenses as a purified compound on a cooled surface, a non-volatile residue of impurities is left behind.
Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

Sublimation is used to purify:

  1. plasma

  2. gases

  3. solids

  4. liquids
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Sublimation is a technique that helps chemists to purify. During sublimation,upon heating, a solid substance is converted to the gas phase without passing through the liquid phase.  A solid is heated under vacuum. The solid volatilizes and condenses as a purified compound on a cooled surface, a non-volatile residue of impurities is left behind.

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

Sublimation can be used to separate a mixture of solids in which:

  1. one sublimes other does not

  2. both sublimes

  3. both does not sublime

  4. sublimation cannot be used for separation
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Sublimation can be used to separate a mixture of solids in which one sublimes other does not. Thus, ammonium chloride can be separated from sodium chloride by sublimation. Ammonium chloride sublimes whereas sodium chloride does not.

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

Sublimation process is used:

  1. to separate mixtures that contain a sublimate with a non-volatile component from a non-sublimate impurity

  2. to separate mixtures that contain a sublimate with a volatile component from a non-sublimate volatile impurity

  3. to separate mixtures that contain a sublimate with a volatile component from a non-sublimate impurity

  4. none of above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Sublimation process is used to separate mixtures that contain a sublimate with a volatile component from a non-sublimate impurity. Thus, ammonium chloride can be separated from sodium chloride by sublimation. Ammonium chloride sublimes whereas sodium chloride does not.

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods
Method of separation by sublimation is limited. 

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The given statement is True.
 Method of separation by sublimation is limited. This method can be used for separation of only those compounds that sublime (i.e, change their state on heating from solid to vapour without passing through liquid state). Examples of sublimable compounds include iodine, ammonium chloride, camphor and naphthalene.

Note: If in the given mixture, none of the compounds is sublimable, then method of separation by sublimation cannot be used.

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

Ammonium chloride is separated from a mixture of sodium chloride and ammonium chloride by the process of:

  1. evaporation

  2. sublimation

  3. fractional distillation

  4. filtration
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ammonium chloride is separated from a mixture of sodium chloride and ammonium chloride by the process of sublimation. Ammonium chloride can be sublimed whereas sodium chloride cannot be sublimed. When a mixture of sodium chloride and ammonium chloride is heated, ammonium chloride changes its state from solid to vapour. The vapours of ammonium chloride are then condensed on cold surface. Sodium chloride is left behind.

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

By which process can we separate camphor from ammonium chloride?

  1. Filtration

  2. Sublimation

  3. Dissolution and evaporation

  4. Distillation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The mixture of camphor and ammonium chloride cannot be separated by sublimation method since both are volatile substances. Thus the mixture is dissolved in water. Ammonium chloride is soluble in water while camphor is not thus the water containing ammonium chloride is decanted in another beaker. Thus camphor is obtained and now the solution is evaporated to separate ammonium chloride. The solution containing ammonium chloride is heated and boiled off the ammonium chloride is left behind

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

By which method can ammonium chloride be separated from sand?

  1. By hand picking

  2. By filtration

  3. By sublimation

  4. By diffusion
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Sublimation is used to separate a mixture of sand and ammonium chloride. Sublimation is a separation process that entails heating a mixture of solids, where one of the solids transitions from solid to gas without passing through the liquid state. The vaporized solid is then reclaimed by cooling the vapor which reverts back to its initial solid state.

In the case of ammonium chloride and sand, ammonium chloride is the sublimate and changes to vapor

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

The mixture of X and Y were taken in a condenser flask and were then heated. After keepint it for cooling, crystals of Y were found on the walls of the flask and X was present as such at the bottom of flask. Identify X and Y:

  1. $X= NaCl, Y= KCl$
  2. $X= Anthracene, Y=Naphthalene$
  3. $X=NaCl, Y= Naphthalene$
  4. $X=Anthracene, Y=NaCl$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Since crystals of $Y$ were formed on the walls of flask hence it must be some compound which sublimates on heating, and there was no effect on the $X$ so $X$ must be compound with high boiling point. The only combination with these properties are $X=NaCl$, $Y=Naphthalene$

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

Put the following 6 steps for separating sand and salt into the correct order:

A.  Heat filtrate to evaporate off the solvent (water).

B.  Pour salt water filtrate into an evaporating basin on a tripod over a Bunsen burner.

C.  Filter to remove the insoluble sand.

D.  Place the sand/salt mixture into a beaker and add water.

E.  Allow basin to cool & collect salt.

F.  Stir to allow the salt to dissolve in the water.

  1. $CDFBAE$
  2. $CDBAFE$
  3. $DFCBAE$
  4. $ABCDEF$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The correct order of the process would be DFCBAE as shown below.

D.  Place the sand/salt mixture into a beaker and  add water

F.  Stir to allow the salt to dissolve in the water

C.  Filter to remove the insoluble sand

B.  Pour salt water filtrate into an evaporating basin on a tripod over a Bunsen burner

A.  Heat filtrate to evaporate off the solvent (water)

E.  Allow basin to cool & collect salt

Multiple choice chemistry separation of matter sedimentation, decantation and filtration other methods of separation separation methods

Which of the following is a seperation technique to seperate potassium chloride and ammonium chloride?

  1. Distillation

  2. Evaporation

  3. Condensation

  4. Sublimation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A mixture of ammonium chloride and potassium chloride can be separated using the process of sublimation. You must also note that both these substances are sublimable. This technique is quite feasible in this case as the sublimable temperatures of ammonium and potassium chloride differ widely. Between the two, ammonium chloride has lower sublimable temperature. Therefore, it sublimes first followed by potassium chloride.