NITROGEN 



43 



cylinder just below the surface of the water, as shown in Fig. 

 20. After the candle is extinguished, remove it by thrusting the 

 hand through the water into the cylinder without admitting any 



Fig. 20. Preparation of nitrogen. 



air. While still under water, cover the cylinder with a glass plate 

 and remove from the trough. Then make the following tests : 



(i) Insert a burning splinter into the cylinder of N. Observe 

 the result. (2) Place a little sulfur in the deflagration spoon, 

 ignite, and insert in the cylinder of N. Observe the result. 

 (3) With a ruler, measure the height of the cylinder and the 

 amount of water left in the cylinder. 



Questions. ( i ) What is the color of N ? ( 2 ) Odor ? ( 3 ) Com- 

 pared with air is it a heavy or light gas? (4) Is it combustible? 

 (5) Does N support combustion ? (6) Is N an active element ? 

 (7) What portion of the cylinder is filled with water in the 

 preparation of N ? (8) What portion of the cylinder is filled 

 with N? (9) What portion of the cylinder did the O occupy ? 

 (10) What becomes of the products of the combustion of the 

 candle? (n) What do these experiments prove in regard to 

 the element N ? (12) Complete the following table : 



Name of Combin- Combus- Supporter of Where 



element. Symbol, ing wt. Color. Taste. Odor, tible. combustion, found. 



Oxygen 

 Nitrogen 

 Hydrogen 

 When the candle is burned, the oxygen of the air in the cyl- 



