Tag: other methods of separation

Questions Related to other methods of separation

Sublimation is the process of separating a liquid from its solution by evaporating it and then condensing its vapour.

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

  1. True

  2. False

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Correct Option: B
Explanation:
The answer is $false$.

Sublimation is the process by which a solid directly converts into gas without undergoing liquid state or vice versa. 
For example, naphthalene.

A $40\ ml$ of a mixture of ${ H } _{ 2 }$ and ${ O } _{ 2 }$ at $18\ ^0C$ and $1\ atm$ pressure was parked so that the for water was complete. The remaining pure gas had a volume of $10\ ml$ at 18 $^0C$ and $1\ atm$ pressure, the remaining gas was ${ H } _{ 2,}$ the mole fraction of ${ H } _{ 2 }$ in the $40\ ml$ mixture is:

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

  1. $0.75$

  2. $0.5$

  3. $0.65$

  4. $0.85$

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Correct Option: A

The rate of evaporation increase with increasing:

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

  1. surface area

  2. temperasture

  3. humidity

  4. wind speed

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Correct Option: A,B,D

Sublimation cannot be used for purification of 

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

  1. Urea

  2. Camphor

  3. Benzoic acid

  4. Naphthalene

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Correct Option: A

Naphthalene is a volatile solid. It is best purified by:

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

  1. Crystallisation

  2. Distillation

  3. Steam distillation

  4. Sublimation

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Correct Option: D
Explanation:

Sublimation is the process in which a particular solid is converted into gas without changing into liquid. Naphthalene is volatile. It sublimates at room temperature without converting into liquid.

Sublimation is a process in which a solid.

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

  1. Changes into another allotropic form

  2. Changes into liquid form

  3. Changes into vapour form

  4. None of the above

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Correct Option: C
Explanation:

Sublimation is a specialized change of state when a solid substance skips the liquid phase and moves directly into the gas phase. This occurs because the substance absorbs energy so quickly from the surroundings that melting never occurs.

Examples:

  •  "Dry ice" or solid carbon dioxide sublimes.
  •  Snow and ice can sublime in the winter months without melting.

Anthracene is purified by?

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

  1. Filtration

  2. Distillation

  3. Crystallisation

  4. Sublimation

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Correct Option: D

A mixture of water and NaCl can be separated by?

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

  1. Sublimation

  2. Evaporation

  3. Decantation

  4. Filtration

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Correct Option: B
Explanation:

Salt dissolves in water. There is a high difference in their boiling point, so evaporation can be used to remove the water to obtain salt. The water vapours that evaporates can be condensed to form water. Salt is left behind as residue during evaporation.

How are the following separated ?
Lead sulphate from a mixture of lead sulphate and lead chloride ?

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

  1. distillation

  2. filtration

  3. chromatography

  4. evaporation

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Correct Option: D
Explanation:

Lead sulphate is insoluble in water whereas lead chloride is soluble. By dissolving the mixture of lead sulphate and lead chloride in water we can separate the two. After dissolving the mixture in water, lead sulphate can be obtained as the solid that's left behind. Lead chloride can be recovered by evaporating the solution.

Name a technique used to separate : Carbon and sulphur

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

  1. sublimation

  2. filtration

  3. distillation

  4. magnetic

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Correct Option: A
Explanation:

By sublimation - Sulphur on heating directly converts into its gaseous state, which can later be converted into its solid state again. Carbon does not show the same property.