Chemical Change and Energy 325 



FIG. 172. The part of the match in the middle of the flame does not burn. 



and air rushing in? Can they get hot all at once, or will 

 they have to travel out or up a way before they have time 

 to get hot enough to combine ? 



Application 73. Explain why boiled milk has a different 

 taste from fresh milk ; why blowing on a match will put it 

 out ; why food gets black if it is left on the stove too long. 



Inference Exercise 



Explain the following : 



451. When you want bread dough to rise, you put it in a warm 



place. 



452. Ink left long in an open inkwell becomes thick. 



453. A ball bounces up when you throw it down. 



454. When the warm ocean air blows over the cool land in the 



early morning, there is a heavy fog. 



