A popular chemistry; . hyde, is formedby passing CI through absolute alcohol. It is an oilyliquid which combines with H20, making ChloralHydrate, a white, crystalline substance, much usedto induce sleep. Taken in proper quantities, it isentirely safe, and is exceedingly pleasant in its in-fluence. THE CARBOHYDRATES STARCtJ, WOODY FIBER, AND SUG^R. Fig. 71. 1. STARCH (C6Hl005). Source.—Plants accumulate it, 1, in their roots, asthe carrot, the turnip, etc.; 2, in subterranean stems,as the potato, of which it forms about 2 0 per cent.; 3, in the base of theirleaves, as the onion; 4,in the seed,
A popular chemistry; . hyde, is formedby passing CI through absolute alcohol. It is an oilyliquid which combines with H20, making ChloralHydrate, a white, crystalline substance, much usedto induce sleep. Taken in proper quantities, it isentirely safe, and is exceedingly pleasant in its in-fluence. THE CARBOHYDRATES STARCtJ, WOODY FIBER, AND SUG^R. Fig. 71. 1. STARCH (C6Hl005). Source.—Plants accumulate it, 1, in their roots, asthe carrot, the turnip, etc.; 2, in subterranean stems,as the potato, of which it forms about 2 0 per cent.; 3, in the base of theirleaves, as the onion; 4,in the seed, as corn, ofwhich it forms about65 per cent., the bean,the pea, etc. In allthese it is stored upfor the future growthof the plant. It is keptin its starch form (lestit dissolve in the firstrain), and then turnedto sugar only when theplant needs it in growing. (See p. 196.) Under themicroscope, each vegetable is found to have its pecu-liar form of starch granule, so that in this way anyadulteration is easily detected.*. Potato Starch. * The structure of the grains of starch, is very beautifully displayed byplacing some of them in contact with a drop of concentrated solution ofzinc chloride (tinged with a little free iodine) on the field of the micro- 212 ORGANIC CHEMISTRY Fig. 72. Preparation.—Starch is made from wheat, corn, po-tatoes, etc. The processis essentially the same inall. The potato, for ex-ample, is ground to apulp, and then washedwith cold water. Thestarch settles from thismilky mass as a fine,white precipitate. Properties.—Starch isinsoluble in cold water ; in hot, it absorbs H20,
Size: 1574px × 1587px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade18, booksubjectchemistry, bookyear1887
