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ovember, 1925 I-VDb-STRIAL AiVD ESGINEERING CHEMISTRY 1199 correct heating value when using a monel bomb depends upon the following assumptions:(1) The amount of nitrogen oxidized is small and approximately equal to 1.7 cc. of 0.1 N solution.(2) Since the sulfur originally present in coal as sulfate is very small, it is disregarded and the total sulfur of the coal is assumed to be oxidized to sulfur trioxide.(3) Part of the sulfur trioxide remains as sulfuric acid and the rest goes to form nickel and copper sulfates.(4) The amount of nickel and copper dissolved is in the ratio of 2:l. Method of Making CorrectionsThe procedure used in making the correction will be more easily shown by taking a specific example, such as Run 20.When the bomb washings were titrated, only 0.2 cc. of 0.1 N alkali were required. Since the nitrogen oxidized would require 1.7 cc. alkali, this gives a negative 1.5 cc. In other words, 1.5 cc. of the nitric acid reacted with the monel metal. The 1.5 cc. of nitric acid are equivalent to 1.5 X 0.0016 = 0.0024 gram sulfur. The total sulfur, 0.0290 gram, plus the 0.0024 gram = 0.0314 gram sulfur in the nickel and copper sulfates. The correction is l/$ X 0.0314 X 3975 + '/a X 0.0314 X 4944 = 145 calories. The heating value corrected for copper and nickel dissolved is 6498 -145 = 6353 calories.

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