230 COMMON CHEMICAL PROCESSES 



QUESTIONS 



1. Define combustion. What is a combustible? In common 

 fuels, what elements usually burn ? What substance commonly 

 supports combustion ? Name the compounds generally formed by 

 combustion of fuels in air. 



2. How, in general, may we start combustion? How, after 

 being started, does the process keep itself going on ? By what 

 means may combustion be stopped ? 



3. What is an explosion ? Why is an exploding mixture able 

 to exert so great force ? 



4. What sort of substances burn with a flame ? How do solids 

 burn ? Show why flames are seen when some solids (e.g. wood) 

 are burned. Explain the burning of such substances (e.g. kero- 

 sene, candles, etc.) as furnish light. What is smoke ? 



5. What is meant by the word fire ? In common fires explain 

 each of these : the heat, light, flame, smoke, and ashes. 



6. Explain the meaning of oxidation. What substances com- 

 monly form oxides in this way? What is iron rust? Under 

 what conditions is it usually formed? 



7. What element in the air is needed by animals ? What 

 becomes of this element when it is taken into the lungs ? With 

 what does it unite ? Where ? What does this process supply to 

 the body ? 



8. What is meant by decay ? What sorts of substances usually 

 suffer decay ? 



9. What is a ferment ? Name a common ferment. When a 

 ferment acts upon dextrose what is formed? How is vinegar 

 made? 



10. What sort of a substance is yeast ? Explain the action of 

 yeast in bread making. What gas is formed, and what is its use ? 



11. Explain how disease may be given from one person to 

 another. What is meant by disinfection? What methods are 

 useful ? 



