An Elementary Course of Food Chemistry (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1913. Excerpt: ... Composition of Organic Substances Organic chemistry has developed from the study of products obtained from plant and animal substances. At the close of the 18th century Lavoisier, a French chemist, demonstrated that, when the organic products of vegetable and animal organisms are burned, carbon dioxide and water are always formed. Lavoisier showed also that the component elements of these bodies are generally carbon, hydrogen, and oxygen, and frequently nitrogen. It was believed for a long time that organic substances could not be formed synthetically from the elements, but could be formed only as a result of vital processes. This conception was disproved by Woehler who succeeded in preparing urea from ammonium cyanate in 1828. Since then most of the organic compounds have been artificially prepared. Organic compounds all contain carbon so that organic chemistry is now defined as the study of the compounds of carbon. Carbon forms an exceedingly large number of compounds, over 60,000 in all, so that a study of these must necessarily be made a separate branch of chemistry. The simplest compounds of carbon are the compounds of carbon with hydrogen, called hydrocarbons. Besides these we have compounds of carbon, hydrogen and oxygen, and many which contain nitrogen in addition. Sulphur and phosphorus also enter into the composition of many organic compounds. It is possible to introduce, artificially, almost all of the elements, both metals and non-metals, as constituents of carbon compounds. The number of known carbon compounds is therefore very great. Experiment No. 1.--Composition of Organic Compounds Reading--P. & K., p. 3. N., pp. 1-4. Apparatus.--4 test-tubes, beaker (100cc), crucible, ringstand, burner. Material.--Cane sugar, egg yolk, soda-lime, sodium ...