HO ANSWERS TO PRACTICAL QUESTIONS 



54. Write in double columns the different properties of 

 carbonic anhydride and carbonic oxide. 



1. CO S . 



2. Atomic weight 44. 



3. Specific gravity 1.529. 



4. Will not burn. 



5. A negative poison. 



6. Liquefies at 32, and a pressure 



of 38.5 atmospheres. 



7. Freely soluble in H 2 O. 



8. Forms salts. 



&c., &c. 



1. CO. 



2. Atomic weight 28. 



3. Specific gravity .967. 



4. Burns with a blue flame. 



5. A direct poison. 



6. Has never been liquefied. 



7. Sparingly soluble in water. 



&c., &c. 



1 1 8. i. If chlorine water stands in the sunlight for a 

 time, it will only redden a litmus-solution. Why does it not 

 bleach it? 



Hydrochloric acid is formed, which reddens the lit- 

 mus. 



2. Why do tinsmiths moisten with HC1, or sal-ammoniac, 

 the surface of metals to be soldered ? 



It dissolves the coating of oxide and leaves the surface 

 of the metal free for the action of the solder. 



3. How much HC1 can be made from 25 Ibs. of common 

 salt ? 



Find (i) how much Cl there is in 25 Ibs. of NaCl, and 

 (2) how much HC1 that amount of Cl would make. 



(i). Cl : NaCl : : x : 25 Ibs. 

 35-5 : 58.5 :: x : 25 Ibs. 

 58.5 = 887.5 Ibs. 



x = 15.17094 Ibs. (Cl). 



(2). Cl : HC1 : : 15.17094 Ibs. : x. 

 35-5 : 36-5 : : i5-i794 Ibs. : x. 

 35-5 x - 553-73931 Ibs. 



x - 15.5980056-1- Ibs. (HC1). 



