Question

Ms Mehta, a science teacher gave different mixtures to four groups of students to separate their components.
Which group was not following the correct method?
(A) Group 1 was separating a mixture of ethyl alcohol and water by using separating funnel.
(B) Group 2 was separating a mixture of ammonium chloride and sodium chloride using sublimation.
(C) Group 3 was separating a mixture of iron pins and sand by using a magnet.
(D) Group 4 was separating mud particles suspended in water using sedimentation and decantation.
(E) None of these​

Answer 1

Group A because ethyl alcohol and water are miscible liquids and hence cannot be separated by separating funnel.

Answer 2

Group 1 was not following correct method (A) Group 1 was separating a mixture of ethyl alcohol and water by using separating funnel.

How to separate components of a mixture?

• There are various ways to separate mixture components, different for each kind of mixture.
• In all methods, one of the components have to behave differently from the other so that we can differentiate them.

We can observe in this question,

1. Separating Funnel can be used to separate mixtures which are immiscible and have different densities. Here, water and ethyl alcohol are miscible, so they cannot be separated by separating funnel.
2. Sublimation can be used to separate 2 components one of which can sublime. Here, ammonium chloride is sublimable whereas sodium chloride is not, so this method works.
3. Iron pins will be sticking to the magnet but sand is not ferromagnetic, so this method is correct.
4. Since particles are suspended freely, sedimentation and decantation can be used to make the particles settle down and then can be separated.

Therefore, we can see that Group 1 was not following correct method. The correct method could have been distillation, which is used to separate miscible liquids.