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Common terms and phrasesacetone added aldehyde alkali ammonium amount apparatus aqueous atoms benzene boiling bromine bulb Calc calculated carbon carbon disulfide Chem chemical chloride color compound concentration condensation cone constant containing cooling copper coumarane crystals curve determined diameter dilute dioxide dissolved distilled dried electrons equation ester ether experiments extracted filtered filtrate flask formula fraction glacial acetic acid glass heated hydrobromic acid hydrochloric acid hydrogen hydrolysis insoluble iodide iodine ketones liquid measurements melting mercury method methyl alcohol mixture molecules molybdenum mutarotation nitrate nitrogen obtained octet oxide oxygen particles phenol phenylhydrazone potassium precipitate prepared present pressure reaction recrystallized rotation salt sample saponin saturated selenic acid semicarbazide separated sodium hydroxide soluble solution solvent starch Subs substance sulfate sulfide sulfuric acid surface tension Table tellurium temperature theory thermometer tion tube valence values vapor velocity volume washed weight yellow yield zinc Popular passagesPage 933 - Postulate 7. The properties of the atoms are determined by the number and arrangement of electrons in the outside layer and the ease with which they are able to revert to more stable forms by giving up or taking up electrons, or by sharing their outside electrons with atoms with which they combine. The tendencies to revert to the forms represented... Page 933 - A stable pair may also be held by (a) a single hydrogen nucleus; (b) two hydrogen nuclei; (c) a hydrogen nucleus and the kernel of another atom; (d) two atomic kernels (very rare). "10. The next most stable arrangement of electrons is the octet, that is, a group of eight electrons like that in the second shell of the neon atom. Any atom with atomic number less than... Page 932 - These atoms thus have the symmetry of a tetragonal crystal. 2. The electrons in any given atom are distributed through a series of concentric (nearly) spherical shells, all of equal thickness. Thus the mean radii of the shells form an arithmetrical series 1, 2, 3, 4, and the effective areas are in the ratios 1:2": 32:42. Page 933 - Two octets may hold one, two, or sometimes three pairs of electrons in common. One octet may share one, two, three or four pairs of its electrons with one, two, three or four other octets. One or more pairs of electrons in an octet may be shared by the corresponding number of hydrogen nuclei. No electron can be shared by more than two octets. Page 932 - The first shell thus contains 2 cells, the second 8, the third 18, and the fourth 32. 4. Each of the cells in the first shell can contain only one electron, but each other cell can contain either one or two. Page 131 - A new method for the purification of gallium salts was worked out in some detail. This rests upon the convenient fact that gallium trichloride sublimes and distils at a low temperature, whereas the other chlorides likely to be associated with it are much less volatile. The method rested, therefore, upon fractional distillation... Page 133 - The method of separating gallium from indium by means of the different solubilities of the hydroxides in caustic alkali was tested without success; much more promising results were obtained by the electrolytic method. The compressibility of solid gallium... Page 762 - The length of this insulation has already been specified. Any device used to close the top of the boiling tube must allow a free opening for equalization of pressure. (2) Purity of Sulphur. — The sulphur should contain not over 0.02 per cent of impurities. It should be tested to determine whether selenium is present. (3) Radiation Shield. — The radiation shield consists of a cylinder open at both ends and provided with a conical umbrella above. The cylindrical part is to be 1.5 to 2.5 cm larger... Page 761 - Boiling Apparatus. — The boiling tube is of glass, fused silica or similar material, and has an internal diameter of not less than 4 nor more than 6 cm. The length must be such that the length of the vapor column measured from the surface of the liquid sulphur to the level of the top of the insulating material surrounding the tube shall exceed the length of the thermometer coil by at least 20... Page 979 - If molecules of this type, such as butyric acid (C3H7COOH), are put in a two phase system consisting of a polar liquid such as water, and a nonpolar liquid such as octane, then the free energy of the interface will be less when the transition from one liquid to the other is made by molecules of butyric acid, with their polar ends turned toward the water, and their nonpolar ends turned toward the octane, since in this way the abruptness of the transition is decreased. |