Three mixtures A, B and C are obtained by stirring three different solids in water taken in separate beakers. When mixture A is allowed to stand for some time, then its particles settle at the bottom of the beaker. When a beam of light is passed through mixture A in a dark room, the path of light becomes visible when observed from the side of the beaker. When mixture B is allowed to stand for a considerable time, even then its particles do not settle down. Mixture B, however, scatters the beam of light just like mixture A. The particles of mixture C do not settle down on keeping and it also does not scatter a beam of light passing through it.

(a) What are the mixtures like A known as?


(b) What are the mixtures like B known as?


(c) What are the mixtures like C known as?


(d) Name the phenomenon exhibited by A and B which occurs on passing a beam of light through them.


(e) Name one mixture each which is like (i) A (ii) B, and (iii) C.

(a) Suspensions

(b) Colloids


(c) True solutions


(d) As A and B are suspensions and colloids, they will show Tyndall effect


(e) (i) Example of suspension is Chalk-water mixture


(ii) Example of colloid is Soap solution


(iii) Example of true solution is Salt solution


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