State board questions and answers / by R. Max Goepp.
- Goepp, R. Max (Rudolph Max), 1866-1950
- Date:
- 1911
Licence: Public Domain Mark
Credit: State board questions and answers / by R. Max Goepp. Source: Wellcome Collection.
Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.
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![Find the weight and the volume of hydrogen contained in 17 grams of NH3. Seventeen grams of NH3 represents 14 gm. of N and 3 gra. of H. One gram of hydrogen under standard temperature and pressure occupies a volume of n. 16 liters, therefore, 3 gm. of hydrogen would measure 3 X 11.16 liters = 33-48 liters. Write an equation representing the reaction for making barium sulfate from sodium sulfate. How many grams of sodium sulfate are required to yield 2.33 grams of barium sulfate by this process (atomic weight of barium, 137)? Na^SO, + BaCl2 = BaS04 + 2NaCl. 142 grams yield 233. To produce 233 gm. of barium sulfate there is required 142 gm. of sodium sulfate, therefore: 233 '• 2-33 : : 142 : x or 1.42. BaS04 BaS04 NaaS04 Na2S04 Answer: 1.42 grams of sodium sulfate are required. Calculate the per cent, of each constituent present in sulfuric acid (atomic weight of sulfur, 32). H2S04 is the molecular composition of sulfuric acid, which represents 2 parts of hydrogen, 32 parts of sulfur and 64 (4X16) parts of oxygen by weight. Therefore, the molecular weight of sulfuric acid would be 2 + 32 + 64=98; hence, 100 parts (per cent.) would be found by the following calculations: 98 : 100 98 : 100 98 : 100 2 : x = 2.04+ per cent, hydrogen. 32 : x = 32.65+ per cent, sulfur. 64 : x = 65.30+ per cent, oxygen. What is the percentage composition of NaNOs? Na = 23 parts by weight. N =14 parts by weight. 03 = 48 parts by weight. 85 molecular weight. 85 85 85 100 100 100 23 : x = 27.05+ per cent, sodium. 14 : x = 16.47+ Per cent, nitrogen. x = 56.47+ per cent, oxygen. The skeleton of a man weighs 24 pounds and contains 58 per cent, of calcium phosphate, Ca3(P04)2. Find the weight of phosphorus present (atomic weight of Ca, 40; of P, 31). 100 per cent. : 58 per cent. : : 24 lbs. : x or 13.92 lbs. of Cag(P04)2 contained in the 24 lbs. Ca3(P04)2 = Ca3 X 40 = 120] P2 X 31 = 62 [-310 the molecular weight of 08 X 16 = 128) Ca3(P04)3 contains 62 parts of phosphorus. Therefore, 310 : 13.92 : : 62 : x or 2.784 lbs. of phosphorus, which is the answer.](https://iiif.wellcomecollection.org/image/b21173709_0044.jp2/full/800%2C/0/default.jpg)
