EXERCISE 33 

 WHAT ARE SOME OF THE PROPERTIES OF CARBON DIOXIDE? 



Materials. Test tubes ; hydrochloric acid ; chips of marble ; apparatus used in Exercise 30 ; 

 bottles ; candle. 



Directions. Generate several test tubes of carbon dioxide by the action of hydrochloric acid on 

 marble, using the apparatus shown on page 64 of "Elements of General Science." This may be 

 done by groups of students working together. Test the gas by use of lime water to see if it is 

 carbon dioxide. 



a. What is the color and odor of the gas ? (If the gas is not washed by shaking with water, 

 the odor of hydrochloric acid will be detected.) 



b. Is it lighter or heavier than air ? To determine this, hold a flaming match over a bottle of the 

 gas and then invert the bottle over the flame of the match. What does the result show ? 



c. Does the gas burn ? Does it support combustion ? 



d. Fill a bottle with carbon dioxide. In another bottle place a burning candle. Then pour the 

 carbon dioxide upon the candle. Explain results. 



Additional problems. Weigh a beaker upon a balance ; then leave the exact weights used upon the scale- 

 pan. Pour carbon dioxide into the beaker and replace the beaker upon the balance. Explain any difference 

 in weight. 



Fill a large container with carbon dioxide ; then pour the gas down an inclined trough which holds 

 several very short burning candles. What happens ? Why ? 



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