COMMON COMPOUNDS OF OTHER ELEMENTS 279 



Chlorides. - - To test for a chloride, add a few drops of 

 nitric acid to a water solution of the salt and then add a 

 few drops of silver nitrate solution. If the salt used is 

 a chloride, there will be a white precipitate of silver chlo- 

 ride formed. When exposed to the sunlight, this precipi- 

 tate turns black. 



QUESTIONS 



1. Name four substances which are not combustible. 



2. Why does a substance which is completely oxidized not 

 burn? 



3. Which is the most important acid? Why? 



4. In case an acid is spilled on clothing, what would you use 

 to neutralize the acid? 



5. Sometimes solids will show an acid reaction. What com- 

 mon substance would you suggest to neutralize the acid ? 



6. Common salt is a compound of sodium and chlorine. Sug- 

 gest a way to separate the sodium from the chlorine. 



