1917 



Comprehensive Examination 



CHExMISTRY 



Monday, September 17 2-5 p.m. 



A teacher's certificate covering laboratory instruction must be presented as a part of 

 the examination unless the laboratory notebook is to be presented at a laboratory 

 examination. 



Answer ten questions as indicated below. 



Attach to the answer, in each case, the number and letter used in the printed paper. 



Part I 



(Answer all questions in Part I.) 



1. Define, and give at least one example of (1) diacid base, (2) acid salt, (3) redu- 



cing agent, (4) anion, (5) atom, (6) molecule. 



2. a) Define and give three examples, of neutralization, describing the ionic 



changes involved in the reactions. 



h) Define and give an example of hydrolysis. How can the litmus reaction 

 of the water solution of a normal salt be predicted from its composition ? 

 Illustrate your answer by an example of a salt having an acid reaction 

 and of another having a basic reaction. 



3. a) State Gay-Lussac's law of combining gas volumes, and illustrate with an 



example. State the hypothesis which serves to explain the facts 

 generalized by this law. 



b) 30 grams of chlorine are to be united with hydrogen. What volume of 

 hydrogen is required at 0° C. and 760 mm., and what volume of hydro- 

 gen chloride results under the same conditions? (CI = 35. 5, H=l.) 



Note. — A liter of chlorine at 0° C. and 760 mm. weighs 3 . 22 grams, and a liter of hydrogen 

 0.09 gram. 



4. a) Name and describe three allotropic forms of sulphur, and tell how each is 



prepared. 



b) Give the names and formulas of the two most important oxides of sulphur, 

 and show by means of chemical equations what occurs when each of 

 these oxides is treated with water. 



5. Write equations for the following reactions, using formulas throughout. The 



equations must be properly balanced to receive credit: 



a) Lead nitrate and hydrogen sulphide = ? 



b) Copper and sulphuric acid (hot, concentrated) = ? 



c) Phosphoric acid and barium hydroxide = ? 



d) Sodium carbonate and acetic acid= ? 



e) Ammonium chloride and calcium hydroxide = ? 



(SEE NEXT PAGE) 

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