A YEAR IN SCIENCE 27 



to produce such a result? How do you account for 

 it? What must have been the condition to cause the 

 liquid to rise in the tube when the belljar was 

 removed? What does this exercise teach? Compare 

 the rate of diffusion of gases with that of liquids; of 

 solids. Compare the rate of diffusion of liquids with 

 that of solids. 



Exercise 8. Mixing of Alcohol and Water. 

 Object: To determine the result of mixing equal 

 volumes of alcohol and water. 



Apparatus 



Alcohol 96% Burette, 100 c.c. 



Distilled water Clamp 



Directions : Over the small end of the burette place 

 a small rubber tube. Close the tube tightly with the 

 clamp. Into the open end of the burette pour distilled 

 water to the height of the 50 c.c. mark. Then carefully 

 and slowly pour into the tube 50 c.c. of alcohol. Note 

 carefully the height of the two liquids. By means of 

 the thumb close the burette and mix the liquids thor- 

 oughly by repeatedly inverting the tube. Observe 

 again the height to which the liquids rise. What does 

 this condition show? How do you account for it? 



