EXERCISE 48 A 

 DOES ICE EVAPORATE? 



Materials. Metal cup ; balances. 



Directions. If Exercise 48 is performed during the winter, this exercise will be of much interest 

 and can be done at the same time. Put water in a tin cup and set it outside to freeze. When the 

 water is completely changed to ice, weigh it quickly and again set outside, so that it will remain 

 frozen. On the next day and several following days weigh it again and record the results. What 

 conclusion do you draw ? 



Additional problems. Why will wet clothes dry even if they are exposed to freezing weather ? 

 What is the explanation of the fact that snow disappears during a period of days when the temperature 

 is constantly at or below freezing ? 



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