WATER 

 EXPERIMENT 27. PRECIPITATION AND FILTRATION 



(a) In precipitation a solid and a liquid are formed from 

 the mixing of two liquids. - 



FIG. 27 Precipitation. 



Put three teasnoonfuls of lead nitrate in a test tube and 

 then add about three times as much water. 



In another test tube put about the same quantity of salt 

 water. Now pour the two solutions into a beaker and note 

 that a white solid has been formed from the mixing of the 

 two liquids (Fig. 27). 



The solid is called a precipitate and the action is called 

 precipitation. 



Can you suggest why it is unwise to pour medicines and 

 unknown liquids down drain pipes ? 



(b) Fold a piece of filter paper as directed by your in- 

 structor and place it in a funnel (Fig. 28). Then pour 



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