Pages 



11. a) State the action of yeast on sugar. 



b) Describe the function of baking powder in cooking. 



c) Give one process for softening hard water. 



d) Why does the flame of a gas stove sometimes "strike back" ? How can 



this difficulty be remedied ? 



12. a) In the smelting of iron ore, what materials enter the blast furnace, and 



what is the function of each ? 

 b) What name is given to the metal produced by the blast furnace, and how 

 does it differ in physical properties and in chemical composition from 

 the product of the Bessemer converter ? 



13. a) Outhne the manufacture of sulphuric acid by the contact process. 



b) Indicate the importance of this acid in the manufacture of miUtary explo- 

 sives by citing two processes in which it is necessary. 



14. Barium carbonate is treated with a quantity of boiUng dilute sulphuric acid 



just sufficient for complete reaction. Using the language and symbols of the 

 ionization theory wherever pertinent, describe what takes place. 



15. What experiment would you make to distinguish between: 



a) Sodium chloride and ammonium chloride ? 



b) Potassium iodide and potassium bromide ? 



c) Glucose and cane sugar ? 



d) Copper oxide and manganese dioxide ? 



e) Chlorine water and bromine water ? 



53 



