MATTER AND ITS PROPERTIES 55 



are composed is called organic matter. The blood of 'an 

 animal and the sap of a tree are organic matter. Grains of 

 sand and drops of pure water are inorganic matter; they have 

 none of the physiological properties. 



EXERCISES 



1. Name some bodies composed wholly or in part of silver; paper; 

 stone; iron; rubber. 



2. Name the principal substance in a book; a stove; a desk; a 

 tumbler; a shoe. 



3. By what words would you describe a piece of chalk? 



4. What are the characteristics of salt? 



5. Name the properties of lead. Tell why Ex. 3 and Ex. 4 are 

 of the same kind as Ex. 5. 



6. How many centimeters are there in 3 m. 4 dm. 5 cm.? 



7. Write 1,246 cm. in terms of several different units. 



8. (a) A tank is 1 m. deep, 1.5 m. long, .75 m. wide. Find its 

 contents in cubic meters. 



(6) Write the dimensions in decimeters and find its contents in 

 cubic decimeters. 



(c) What weight of water would fill the tank? 



9. Why do people who are standing in a moving car tend to fall 

 forward if the car stops suddenly? 



10. What is the only safe way to alight from a moving vehicle? 

 Give reasons. 



11. Describe the effect on upright bodies in a wagon, when it sud- 

 denly turns a right angle. 



12. Arrange under the two headings organic matter and inorganic 

 matter the following substances : an apple, a pebble, silk, cotton, 

 chalk, paper, salt, sugar, wood, brick, bread, granite, silver, milk, ice. 



