152 



12. What weight of zinc is required to make 100 liters of hydro- 

 gen, at 10 and 750 mm., by displacement from hydrochloric acid 

 (p. 53)? 



13. What are the relative volumes of the factors and of the 

 products in the interaction between: (a) turpentine vapor and 

 chlorine: (b) oxygen and carbon disulphide vapor (giving S0 2 

 and C0 2 )? 



14. What are the relative volumes of the products in the de- 

 composition of: (a) mercuric oxide; (b) chlorine monoxide C^O 

 (chlorine and oxygen are formed)? 



15. What are the relative volumes of the volatile substances 

 concerned in the action of water vapor on iron (p. 102)? 



16. Using the relative volumes in which oxygen and hydrogen 

 combine to form steam, prove that each molecule of free oxygen is 

 composed of at least two atoms (c/. p. 105). 



17. (a) Calculate the weight of chlorine dissolved by 100 c.c. 

 of water at room temperature (p. 143). (b) In half -saturated 

 chlorine-water, what is the concentration of hypochlorous acid 

 (p. 145)? 



