142 FIRST YEAR COURSE IN GENERAL SCIENCE 



154. The Law of Conservation of Matter. A body 

 may be destroyed by burning, or may disappear by evapo- 

 rating, but the matter of which it was composed still exists 

 - perhaps in some different state or united with other mat- 

 ter to form a new substance. This is known as the Law of 

 Conservation of Matter. The law, briefly stated, is this: 

 the quantity of matter in the universe is 

 constant; or in other words, matter is 

 indestructible. 



When an element is completely 

 burned, or oxidized, the product (that 

 is, the new substance formed) weighs 

 more than the original. To the weight 

 of the element that was burned is added 

 the weight of the oxygen. Twelve 

 grams of carbon completely burned give 

 forty-four grams of carbon dioxide. 



If a solid, in burning, forms chiefly 

 gases, the residue (that is, the solid 

 remaining after combustion ceases) 

 through ThiiT~siit and is weighs less than the original, because a 

 pushed up to the top, t of the matter has passed off as 



where it is lighted. 



FIG. 71. BUNSEN 

 BURNER 



Inside, at the bottom 

 of the upright tube, is a 

 small tube with a narrow 

 slit. The gas comes 



gaseous oxides. Wood is a fuel which 

 illustrates this fact. The ashes weigh 

 less than the original wood. 



155. The Law of Definite Pro- 

 portions. Any given compound is 

 always made up of the same elements in 

 the same definite proportions by weight. 

 In combustion 12 grams of carbon will 

 unite with 32 grams of oxygen, or 6 

 grams of carbon with 16 grams of oxygen, and there will be 

 no remainder of carbon or oxygen. But if there are 13 grams 

 of carbon and only 32 grams of oxygen, one gram of carbon 

 will remain uncombined. The same law holds true for 



When the holes at the 

 base of the upright tube 

 are open, air enters and 

 mixes with the gas before 

 it reaches the top. 1. 

 How does that affect 

 combustion? 2. If the 

 holes are open, the 

 flame is pale blue; if 

 closed, it is luminous. 

 Which is like the flame 

 of a gas stove? 



