CARBON 71 



10. For what purposes is coke used? 



11. Where are the best graphite mines? 



12. What are the uses of graphite? 



13. How are lead pencils made ? 



14. Diamond and coal are both carbon. What 

 causes the great difference in the market values of these 

 two substances? Three reasons. 



15. Where are the best diamond mines located? 



16. Do you know how diamonds are mined? Look 

 it up and bring this information to class with you. 



17. How is carbon dioxide produced? 



18. Is it necessary to life? 



19. Is it poisonous? 



20. Would too much of it prove fatal to life ? Why ? 



21. Explain fully why people and other animals are 

 sometimes killed in going down into old wells and 

 mines. 



22. What is the test for the presence of carbon 

 dioxide ? 



23. Is there any soda in ' ' soda water ' ' ? 



24. Whence then does it receive its name? 



25. What causes the effervescence of "soda water"? 



