58 



LABORATORY MANUAL 



the flask to cover the zinc. What action is observed? 

 This is a chemical action between the zinc and the 



Fig. 20. 



acid. The gas given off is hydrogen. Allow the gas 

 to escape from the delivery tube for a few seconds. 

 Why? Fill a number of bottles with hydrogen by the 

 downward displacement of water. Keep the bottles 

 inverted. 



1. Examine the hydrogen in one of the bottles. Has 

 it any color ? Odor ? 



2. With the mouth downward, thrust into a second 

 bottle of hydrogen a lighted splinter. What is the 

 result? Docs the splinter continue to burn? Does the 

 hydrogen burn? If so, what is the color of the flame? 

 Examine the sides of the bottle? What do you find 

 there ? Where did it come from ? What is the oxide of 

 hydrogen? 



3. Allow a third bottle of hydrogen to stand mouth 

 upward for three minutes. Then insert a lighted splin- 

 ter. Is the hydrogen still there? Is hydrogen lighter 

 or heavier than air? 



