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LABOEATORY MANUAL 



Thistle tube 

 Glass cylinder 

 Metric rule 



Apparatus 



Saturated solution of 



copper sulphate 

 Distilled water 



Directions: Fill the glass cylinder two-thirds full 

 of distilled water. Into the cylinder place the thistle 

 tube with the bulb upward. When the water is quiet, 

 slowly pour through the thistle tube 50 cubic centi- 

 meters of copper sulphate solution. 

 This must be done as carefully as 

 possible to avoid mixing the liquids. 

 What is now the relative positions 

 of the liquids ? Is there a sharp line 

 of separation between the liquids? 

 Why is the copper sulphate solution 

 placed on the bottom of the glass 

 cylinder? Measure accurately with 

 a metric rule the height of the 

 copper sulphate solution. Record 

 observations and allow the experi- 

 ment to remain undisturbed until 

 the next recitation period. Then 

 repeat the observations made above. 

 5. What changes? In conclusion, what 



have you learned from this experiment? 



Exercise 5. Diffusion of Liquids through a Mem- 

 brane. 



Object : Will liquids diffuse if separated by an 

 animal membrane? 



