2 VETBEINAEY STATE BOAED 



temperature. Theoretically, at 273 degrees below zero (absolute 

 zero) the gas becomes nothing, and for each degree of rise in tem- 

 perature it expands ^K of the volume which it occupied at 0° C. ; 

 hence 273 volumes of air at 0° C. becomes 274 volumes at 1° C, 

 275 at 2° C, etc. 



Describe the process of electro-plating. 



This process depends upon electrolysis, that is, the decomposition 

 of a chemical compound, the electrolyte, into its constituent parts, 

 called ions, by an electric current. In a battery or in an electro- 

 lytic bath, the metallic, or electropositive ion is carried with the 

 current through the electrolyte. Similarly, when a chemical salt 

 is electrolysed, the metallic base is carried to the cathode (the nega- 

 tive pole of the battery) . Therefore, by attaching the object to be 

 plated at the cathode in a bath composed of a silver, gold or copper 

 solution, it will become coated, or plated, with silver, gold or copper. 



Define evaporation, electrolysis, amorphism, dialysis. 



Evaporation is the process of converting a substance, especially 

 a liquid, into a vapor. 



Electrolysis — see answer to preceding question. 



Amorphism relates to the non-crystalline character of some 

 substances, such as starch and glue. 



Dialysis is the passing of a dissolved substance through a dia- 

 phragm of parchment into another liquid. 



Convert (a) 104° F. to its equivalent in Centigrade degrees, (b) 38° C. 

 to Fahrenheit scale. 



(a) (104° P. — 32) X 5 = 40° C. 



(b) (38° C. X |) + 32 = 100.4° F. 



iNORGAisnc Chemistey 

 Define chemistry. 



Chemistry is the science which treats of the properties and 

 composition of substances, their changes in composition and the 

 phenomena attending such changes. The subject of chemistry is 

 divided for convenience into inorganic, organic and physiologic. 



State the difference between a chemical and a physical change, with 

 an example of each. 

 A chemical change is one occurring in the molecules of matter 

 in which the substance or substances lose their identity by the for- 

 mation of new substances. Example: Paper, when burned, yields 

 carbon dioxide, water and some charcoal. 



A physical change is one occurring in a mass of matter in which 



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