Assignment -chapter Separation of substances

Q- How can you separate the mixture of iodine and sand?  Explain and draw the diagram also.

Answer1-  Take a mixture of sand and iodine in a china dish .
Cover it with an inverted funnel whose narrow end is closed with cotton wool.
Heat the china dish on a wire gauge.

Observation-We observe that on heating iodine sublimates and changes into vapor and rises up.
On coming in contact with walls of funnel it cools down and changes back into solid state
 and sticks to the walls of the funnel and is left behind in the cotton of the funnel.
Result=  Sand and iodine are separated from each other by the process of sublimation.




Question 2   Write an activity to separate mustard oil and water ?Draw the diagram .

Answer 2    
Aim-To separate mustard oil and water.
Material required-Separating funnel, water ,mustard oil, stopcock,beaker and stand.

Procedure-Pour the mixture of water and oil into separating funnel .
  Let it stand for sometime so that separate layers of water and oil  are formed.
Put the stop cock off so that the water slowly starts flowing down and gets collected in the beaker .
Oil will be left behind in separating funnel.
Result-Oil and water are separated by the use of separating funnel.