CHEMISTRY 



Saturday 9-11 a.m. 



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

 of the examination. 



Answer ten questions as indicated below. No extra credit will be given for more 

 than ten questions. 



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



GROUP A. (Answer all questions in this group.) 



1. Give two tests, at least one of which involves chemical change, sufficient to 

 identify each of the following substances: (a) concentrated nitric acid, 

 (b) concentrated sulphuric acid, (c) concentrated ammonium hydroxide, 

 (d) solution of sodium hydroxide. 



2. (a) How should you free moist carbon dioxide gas from water vapor ? 



(b) How should you obtain sulphur from a solution of the element in carbon 

 disulphide? 



(c) How should you liberate copper from a solution of cupric sulphate? 



(d) How should you obtain a specimen of pure nitrogen from a mixture of 

 nitrogen and oxygen ? 



(e) How should you obtain pure specimens of manganese dioxide and potas- 

 sium chloride from a mixture of the two ? 



3. Describe briefly, with or without the help of drawings, the apparatus, mate- 

 rials, operations, and precautions, necessary for the preparation of the 

 following substances in the laboratory: (a) hydrogen, (b) carbon dioxide. 



GROUP B. (Omit 5 or 6.) 



4. Write equations for five of the following reactions, using formulae throughout. 

 (The equation must be absolutely correct to receive credit.) 



(a) Slaked lime -f any acid = 



(b) Cupric oxide -f- hydrogen = 



(c) Ammonium nitrate (heated) = 



(d) Zinc + sulphuric acid (dilute) = 



(e) Ferric sulphate + barium chloride = 

 (/) Ammonia (gas) + hydrogen chloride = 



5. (a) Derive the formula of a compound made up of sulphur 47 . 4 per cent, and 



chlorine 52.6 per cent, which has a vapor density of 67.5 (density of 

 oxygen 16). (Atomic weights Cl, 35.5; S, 32.) 



(b) The specific heat of an element is o . 1 7. What is its approximate atomic 

 weight ? State the law involved. 



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