OXYGEN 95 



it is absorbed into the blood. It is then carried to all 

 parts of the body where the tissues are oxidized and the 

 oxides, chiefly carbon dioxide, are taken by the blood to 

 the lungs or to other organs, where they . are elimi- 

 nated. By heat evolved in the process of oxidation, 

 the bodily temperature is maintained and the energy 

 developed for thought and action. 



Oxygen is slightly soluble in water, about three 

 parts in a hundred. This small amount supports all 

 the varied forms of aquatic life. As stated above, 

 all burning, all decay, are dependent upon oxygen. 

 Thus, in this way, oxygen serves as a purifying agent, 

 for all dead animal and vegetable products are slowly 

 oxidized and thus changed into harmless substances. 



Oxygen is also used by the physician in instances 

 where the patient is unable to inhale a sufficient 

 amount from the air. 



Source. From the fact that oxygen combines so 

 readily with so many different substances, it would 

 seem that the supply would eventually be exhausted. 

 However great the oxidation, the proportion of oxygen 

 in the air is not much affected, for all green plants 

 are continually giving back to the air oxygen, which 

 is thrown off in the process of food making in the 

 plant. 



Questions 



1. Who was Joseph Priestley? What is his claim, 

 to fame? 



2. Name the chief properties of oxygen. 



