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

3

(a)

What is winnowing? Where is it used?

3

(a)

How will you separate husk or dirt particles from a given sample of pulses before cooking?

3

(a)

What is sieving? Where is it used?

3

(a)

Is it possible to separate sugar mixed with wheat flour? If yes, how will you do it?

3

(a)

How would you obtain clear water from a sample of muddy water?

3

(a)

Lemonade is prepared by mixing lemon juice and sugar in water. You wish to add ice to cool it. Should you add ice to the lemonade before or after dissolving sugar? In which case would it be possible to dissolve more sugar? 

3

(a)

You have given a solution of substance X. How will you test whether it is saturated or unsaturated? When a hot saturated solution of a substance is allowed to cool, then what will you get?

3

(a)

The best way to carry out the filtration of the mixture of water and sand is to use filter paper not cloth, why?

3

(a)

Why do we separate substances?

3

(a)

From where does saIt come?

3

(a)

What is sedimentation? Give an example.

3

(a)

Describe the process of sieving. Write one of its uses.

3

(a)

How is common salt obtained from sea water?

3

(a)

How will you separate a mixture of saw dust and sugar?

3

(a)