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Exercises. 1. Which contains more oxygen: (a) a phosphate 

 or a phosphite; (b) a nitrite or a nitrate; (c) a borate or a per- 

 borate? Name the acids corresponding to these six salts. 



2. Make equations for: (a) the roasting of stannic sulphide 

 (SnS 2 ) giving Sn0 2 ; (b) the action of concentrated sulphuric acid 

 on silver giving silver sulphate and S0 2 ; (c) the dissociation of 

 sulphuric acid vapor. 



3. What are the formulae of magnesium sulphite and bisulphite, 

 respectively? 



4. Give two reasons why boiling sulphuric acid, when spilt upon 

 the flesh, causes most serious burns. 



5. By what facts or tests could you recognize concentrated 

 sulphuric acid? 



6. Why is the wooden laboratory shelf commonly " burned " 

 where the sulphuric acid bottle stands? 



7. What would be the reaction between sodium sulphite and 

 sulphuric acid? 



8. How could you distinguish between, and recognize, the sul- 

 phide, sulphite, and sulphate of potassium? 



9. Why is it not desirable to make chamber sulphuric acid of a 

 concentration higher than 60-70 per cent? 



10. Justify the nomenclature in the case of hyposulphurous 

 and persulphuric acids. 





