Separation

Q.

42. What is the difference between sublimation and deposition?

Q.

Why do we need separate mixtures ?Give examples to illustrate your answer

Q.

Why do we need to separate different components of a mixture? Give two examples.

Q. Which method is used to separate the coloured components of a mixture?

1. Filtration
2. Separating funnel
3. Chromatography
4. Distillation

Q. is used to separate the butter from milk.

1. Decantation
2. Sedimentation
3. Churning
4. Evaporation

Q.

Which separation techniques will you apply for the separation of different pigments from an extract of flower petals?

Q. What is the process of heating a liquid to a high temperature and rapidly cooling it (so that the bacteria is killed) called?

1. Chlorination
2. Bacterial disinfection
3. Sublimation
4. Pasteurization

Q. Which of the following materials do we use to separate iron filings from sand?

1. Sand paper
2. Chromatography paper
3. Filter paper
4. Bar magnet

Q.

Which method is used to separate a mixture of common salt and naphthalene powder?

Q.

Mention the principle of hand picking method.

Q.

Clay is separated from water by the method called___________

Q.

Magnets have many applications in our daily lives. Which of the following is an example of using a magnet to separate a mixture?

1. Magnetic door latch on a refrigerator

2. Magnet in hard disks

3. Magnets in junkyards

4. Magnet in a compass

Q.

Iodine dissolve in alcohol to form a/an

1. aqueous solution .

2. non-aqueous solution .

3. definite solution.

4. suspension.

Q.

How will you separate iron nails from saw dust?

Q.

Which of the following gases can be used as a preservative?

1. Oxygen
2. Carbon dioxide
3. Nitrogen
4. Water vapour

Q. The process of separating the constituents of a liquid by agitating it vigorously is called as______

1. Evaporation.
2. Churning.
3. Filtration.
4. Sedimentation.

Q.

Write the principle of separation techniques.

a) Winnowing.

b) Sedimentation and decantation.

c) Loading

d) Crystallisation

e) Magnetic separation.

Q. Which amongst the following separation techniques can be used to seperate salt from seawater?

1. Sedimentation
2. Evaporation
3. Filtration
4. Decantation

Q.

The process of adding chemical substance to help the suspended solid particles settles down faster is known as

1. sedimentation

2. decantation

3. filtration

4. loading

Q.

The salt water can be purified by:

1. Filtering it through a cloth.

2. Stirring it for half an hour.

3. Heating it and thus condensing steam which will give fresh water.

4. Salt water cannot be purified.

Q.

Question 15

Match the mixtures in Column I with their method of separation in Column II.

Q.

Name the method used for the separation of the mixture of common salt from seawater.

Q. is formed when two or more substances are physically combined.

1. Pure substance
2. Mixture
3. Element
4. Compound

Q.

Question 12

Fill in the blanks with appropriate words:
(i) Small pieces of stone can be removed from rice by ___.
(ii) ___ are obtained from stalks by threshing.
(iii) Husk from wheat flour is generally removed by ___.
(iv) The process of settling of heavier particles is called ___.
(v) Filtration is helpful in separating an insoluble ___ from a ___.

Q.

Question 19

You are provided with a mixture of salt, sand, oil and water. Write the steps involved for the separation of salt, sand and oil from the mixture by giving an activity along with the diagram.

Q.

Which separation technique will you apply for the separation of salt from seawater?

Q.

Salt and sugar are

1. Insoluble substances

2. Soluble substances

3. miscible liquids

4. Immiscible liquids

Q.

Why do we separate substances present in a mixture?
i) To separate wanted components from unwanted components.
ii) To remove impurities.

1. Only (i) is correct

2. Both are incorrect.

3. Only (ii) is correct.

4. Both are correct.

Q.

What separation techniques will you apply for the separation of the following:

The different pigments from an extract of the flower petals.

Q.

Separation is done to separate two useful components.

True/False

1. True

2. False