12 Preparation of Substances 



14. How many grams of actual sulfuric acid in a 

 liter of dilute acid of a density of 51.5 Be.? 



15. Where are the phosphate deposits in this 

 country? 



16. Where should a plant for making superphosphate 

 be located? Near the phosphate mines or near the 

 farmer? Give reasons for the answer. 



17. ^^^lat is meant by the terms, " raw rock," " dis- 

 solvd rock " ? 



18. Where is the use of dissolvd rock recommended? 



19. Is calcium sulfate soluble in water? (See text 

 under calcium compounds.) 



20. Write symbols for limestone; slaked lime; quick- 

 lime. 



