82 



ANSWERS TO PRACTICAL QUESTIONS 



Each of these liters of CO 2 weighs 1.97 gm. (see answer 

 to Question 39). Hence the total weight of CO 2 is 114,210.5 x 



1.97 = 224,995 gm. 



CO 3 :C :: 224,995 : x. 



44 : 12 : : 224,995 : x. 

 x = 61.362 T 3 T grams. 

 Or x = 61.362 + , kilograms. 



41. Write in double columns the different properties of 

 carbon dioxide and carbon monoxide ; thus, 



CO 2 is 1, non-inflammable. 



2. Atomic weight 44. 



3. Specific gravity 1.529. 



4. Will not burn. 



5. A negative poison. 



6. Liquefies at 32, and a press- 



ure of 38.5 atmospheres. 



7. Freely soluble in H 2 O. 



8. Forms salts. 



Etc., etc. 



CO is 1, inflammable. 



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. 



Etc., etc. 



I IO 1. If chlorine iv at er stands in the sunlight for a 

 time, it ivill only redden a litmus-solution. Why does it 

 not bleach it ? 



Hydrochloric acid is formed, which reddens the litmus. 



2. Why do tinsmiths moisten with HCl, or sal-ammo- 

 niac, 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 HCl can be made from 25 kilos of com- 

 mon salt ? 



NaCl : Cl : : 25 : x. 



58.5 : 35.5 : : 25 : x. 



x 15.17 kilograms. 



4. What weight of NaCl would be required to form 25 

 kilos of HCl? 



