Tag: dry methods of separation

Questions Related to dry methods of separation

Threshing is a method of separation used to separate:

chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

  1. two useful substances of the same size

  2. harmful substances from the useful ones

  3. the useful substance from the non-useful one

  4. None of these

Show answer
Correct Option: C
Explanation:

A farmer uses the method of threshing to separate the grain from the stalks. The stalks are beaten to separate the grain seeds.

Option (C) is correct.

A few coloured glass pieces that are big in size are mixed with sugar. The easiest way to separate them is:

chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

  1. heat the mixture

  2. add the mixture to water

  3. hand pick the glass pieces

  4. handpick the sugar particles

Show answer
Correct Option: C
Explanation:

Since the size of glass particles is bigger than sugar, so we can easily get rid of those by hand picking.

A very large quantity of mixture contains tiny particles of three different substances X, Y, and Z. They are of the same size, cubical in shape and yellow in colour. X particles are very heavy, insoluble, non-magnetic and contribute 50% of the mixture. Y particles are very light, insoluble, non-magnetic and contribute 40% of the mixture. And Z particles are actually iron pieces. Which of the following methods can separate X, Y, and Z in the fastest manner?

chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

  1. Winnowing - Magnetic separation

  2. Magnetic separation-Winnowing

  3. Sieving-Magnetic separation - Filtration

  4. Handpicking - Sublimation- Sieving

Show answer
Correct Option: B
Explanation:

By magnetic separation- It is used to remove particle Z because Z is iron.

Winnowing-it helps to separate the particle have different weight 
It will help to separate $XYZ$

Threshing is a method of separation used to separate:

chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

  1. two useful substances of the same size

  2. harmful substances from the useful ones

  3. the useful substance from the non-useful one

  4. none of the above

Show answer
Correct Option: C
Explanation:

Threshing is the process of loosening the edible part of grain from the husks and straw to which it is attached. 

It is the step in grain preparation after reaping and before winnowing which separates the grain from the chaff.

Hence, option C is correct.

Winnowing is used for separation of:

chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

  1. homogeneous solid-solid mixtures

  2. homogeneous solid-liquid mixtures

  3. heterogeneous solid-liquid mixtures

  4. heterogeneous solid-solid mixtures

Show answer
Correct Option: D
Explanation:

Winnowing is a farming method developed by ancient people for separating grain from the chaff. It is also used to remove weevils or other pests from stored grain. Threshing, which is the loosening of grain or seeds from the husks and straw, comes before winnowing. It is used for heterogeneous solid-solid mixtures.

Wheat flour can be separated from the wheat bran by:

chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

  1. hand picking

  2. sieving

  3. winnowing

  4. filtration

Show answer
Correct Option: B
Explanation:
Wheat flour can be separated from wheat bran by sieving. Bran is the hard outer layer of cereal grain.
Sieve analysis is a method of determining the particle size distribution of material. 
The process separates fine particles from more coarse particles by passing the material through a number of sieves of different mesh sizes.

Hence, option B is correct.

Winnowing is useful only when:

chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

  1. two solids have different melting points

  2. two solids have different boiling points

  3. two solids have different magnetic properties

  4. two solids have different weights

Show answer
Correct Option: D
Explanation:

winnowing is used to separated heavier and lighter components of a mixture by wind or by blowing air.This process is done by the farmers to separated lighter husk particles from heavier grain particles.

A mixture contains two solids A and B. Solid A is light in weight while solid B is very heavy. Their sizes are almost same. Here, A is the unwanted component. To get pure solid B, which separation method would you suggest?

chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

  1. Sieving

  2. Winnowing

  3. Magnetic separation

  4. Filtration

Show answer
Correct Option: B
Explanation:

Winnowing is a farming method developed by ancient people for separating grain from chaff. It is also used to remove weevils or other pests from stored grain. Threshing, which is the loosening of grain or seeds from the husks and straw, comes before winnowing. It is used for heterogeneous solid-solid mixtures.

Sieving can be used only when the components of the mixture have:

chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

  1. different sizes

  2. different melting points

  3. different boiling points

  4. different specific gravities

Show answer
Correct Option: A
Explanation:

Sieving can be used only when the components of the mixture are of different sizes.

The mixture of the component is added in the sieve. Sieve consists of large number of pores. The particle of small size get easily pass through these pores but the components with large particle size are not able to pass through these pores.
This way sieving separate components of a mixture of different sizes.

Hence, option D is correct.

Some iron fillings are mixed with sand. We can separate them using magnetic separation method. This method is applicable only when:

chemistry mix and separate dry methods of separation process of separating components of a mixture method of separation

  1. magnetic substances are mixed up with non-magnetic substances

  2. magnetic substances are mixed up with magnetic substances

  3. magnetic substances are heated beyond their Curie temperatures

  4. two magnetic substances have equal melting points

Show answer
Correct Option: A
Explanation:

In a mixture of two materials if one have magnetic properties then that material is easily separate by magnet because that material attracted by magnet and other material is not attracted by magnet. 

If both material have magnetic property or both haven't magnetic property then above method doesn't works.