Rhombic Sentence Examples
It sublimes in small rhombic tables or needles, and is slightly soluble in cold water, the solution possessing an acid reaction.
Elie de Beaumont, in his speculations on the relation between the direction of mountain ranges and their geological age and character, was feeling towards a comprehensive theory of the forms of crustal relief; but his ideas were too geometrical, and his theory that the earth is a spheroid built up on a rhombic dodecahedron, the pentagonal faces of which determined the direction of mountain ranges, could not be proved.'
Properties.-Sulphur exists in several allotropic modifications, but before considering these systematically we will deal with the properties of ordinary (or rhombic) sulphur.
Rhombic sulphur may be obtained artificially by slowly crystallizing a solution of sulphur in carbon bisulphide, or, better, by exposing pyridine saturated with sulphuretted hydrogen to atmospheric oxidation (Ahrens, Ber., 1890, 23, p. 2708).
It is readily transformed into rhombic sulphur.
It gradually transforms itself into rhombic sulphur.
In the above instance the sulphur is supposed to be in the solid rhombic modification, the oxygen and sulphur dioxide being in the gaseous state, and the initial and final systems being at the ordinary temperature.
The rhombic faces of the dodecahedron are often striated parallel to the longer diagonal.
The acid is thus obtained in colourless rhombic prisms of the composition C 6 H 8 0 7 +H 2 0.
Again, the pyroxenes, RS103 (R=Fe, Mg, Mn, &c.), assume the forms (I) monoclinic, sometimes twinned so as to become pseudo-rhombic; (2) rhombic, resulting from the pseudo-rhombic structure of (I) becoming ultramicroscopic; and (3) triclinic, distinctly different from (I) and (2); (I) and (2) are polysymmetric modifications, while (3) and the pair (I) and (2) are polymorphs.
AdvertisementThe above may be illustrated by considering the equilibrium between rhombic and monoclinic sulphur.
The overheating curve of rhombic sulphur extends along the curve AC, where C is the melting-point of monoclinic sulphur.
From B the curve of equilibrium (BD) between rhombic and liquid sulphur proceeds; and from C (along CE) the curve of equilibrium between liquid sulphur and sulphur vapour.
When precipitated from solutions it forms red tetragonal crystals, which, on careful heating, give a yellow rhombic form, also obtained by crystallization from the fused substance, or by sublimation.
In the case of sodium dihydrogen phosphate, NaH 2 PO 4 H 2 O, a stable rhombic form is obtained from warm solutions, while a different, unstable, rhombic form is obtained from cold solutions.
AdvertisementAmmonium iodide assumes cubic forms with perfect cubic cleavage; tetramethyl ammonium iodide is tetragonal with perfect cleavages parallel to {100} and {o01} - a difference due to the lengthening of the a axes; tetraethyl ammonium iodide also assumes tetragonal forms, but does not exhibit the cleavage of the tetramethyl compound; while tetrapropyl ammonium iodide crystallizes in rhombic form.
Lead monoxide is dimorphous, occurring as cubical dodecahedra and as rhombic octahedra.
Lead chloride, PbC1 2, occurs in nature as the mineral cotunnite, which crystallizes in the rhombic system, and is found in the neighbourhood of volcanic craters.
It is artificially obtained by adding hydrochloric acid to a solution of lead salt, as a white precipitate, little soluble in cold water, less so in dilute hydrochloric acid, more so in the strong acid, and readily soluble in hot water, from which on cooling, the excess of dissolved salt separates out in silky rhombic needles.
The haematoidin pigment may vary in colour from yellowish or orange-red to a ruby-red, and forms granular masses, rhombic prisms or acicular crystals.
AdvertisementThese frozen metals in general form compact masses consisting of aggregates of crystals belonging to the regular or rhombic or (more rarely) the quadratic system.
Regular crystals expand equally in all directions; rhombic and quadratic expand differently in different directions.
The form of the proglottides is most generally a rhombic or trapezoidal figure.
The scales are sometimes rounded behind, but generally rhombic in shape and more or less elongate; they may be quite smooth or provided with a longitudinal ridge or keel in the middle line.
Light-yellow monoclinic needles of 2KAuC1 4 H 2 O are deposited from warm, strongly acid solutions, and transparent rhombic tables of KAuCl 4.2H 2 O from neutral solutions.
AdvertisementThe solution is filtered and allowed to cool, when colourless rhombic pyramids of the aurocyanide separate.
As the mineral thenardite or mirabilite, which crystallizes in the rhombic system, it occurs in many parts of the world, as in Spain, the western states of North America and the Russian Caucasus; in the last-named region, about 25 m.
About 15% of a volatile oil is obtained by distilling cubebs with water; after rectification with water, or on keeping, this deposits rhombic crystals of camphor of cubebs, C 15 H 26 O; cubebene, the liquid portion, has the formula C15HV4.
It is obtained as rhombic plates by mixing dilute solutions of calcium chloride and sodium phosphate, and passing carbon dioxide into the liquid.
It forms large rhombic prisms, has a somewhat saline taste and is easily soluble in water.
The salt K2S03 2H20 is obtained as oblique rhombic octahedra by crystallizing the solution over sulphuric acid.
The very beautiful (anhydrous) crystals have the habit of a double six-sided pyramid, but really belong to the rhombic system.
It crystallizes from water in colourless rhombic prisms, containing four molecules of water of crystallization, and possesses a very acid reaction.
It crystallizes in the cubical system, often in beautiful octahedra and rhombic dodecahedra.
Crystals of blende belong to that subclass of the cubic system in which there are six planes of symmetry parallel to the faces of the rhombic dodecahedron and none parallel to the cubic faces; in other words, the crystals are cubic with inclined hemihedrism, and have no centre of symmetry.
An important character of blende is the perfect dodecahedral cleavage, there being six directions of cleavage parallel to the faces of the rhombic dodecahedron, and angles between which are 600.
Percussionfigures, readily made on the cleavage-faces, have rays parallel to faces of the rhombic dodecahedron; whilst figures etched with water represent the four-faced cube.
Thallous sulphate, T1 2 SO 4, forms rhombic prisms, soluble in water, which melt at a red heat with decomposition, sulphur dioxide being evolved.
Thallous nitrate, T1NO 31 is obtained as white, rhombic prisms by crystallizing a solution of the metal, oxide, carbonate, &c., in nitric acid.
The "rhombic dodecahedron," one of the geometrical semiregular solids, is an important crystal form.
On boiling gelatinous silica with ammonium polytungstate and evaporating with the occasional addition of ammonia, ammonium silicodecitungstate is obtained as short rhombic prisms. On adding silver nitrate and decomposing the precipitated silver salt with hydrochloric acid, a solution is obtained which on evaporation in a vacuum gives the free acid as a glassy mass.
The chloride crystallizes in colourless rhombic tables of specific gravity 3.9 and is readily soluble in water, but is almost insoluble in concentrated hydrochloric acid and in absolute alcohol.
It crystallizes in shining rhombic prisms from its aqueous solution and as delicate needles from alcohol.
It readily dissolves in ammonia, the solution, on evaporation, yielding rhombic crystals of 2AgC1.3NH 3; it also dissolves in sodium thiosulphate and potassium cyanide solutions.
Ferrous fluoride, FeF21 is obtained as colourless prisms (with 8H2O) by dissolving iron in hydrofluoric acid, or as anhydrous colourless rhombic prisms by heating iron or ferric chloride in dry hydrofluoric acid gas.
Ferrous bromide, FeBr2, is obtained as yellowish crystals by the union of bromine and iron at a dull red-heat, or as bluish-green rhombic tables of the composition FeBr26H2O by crystallizing a solution of iron in hydrobromic acid.
Ferrous sulphate forms large green crystals belonging to the monoclinic system; rhombic crystals, isomorphous with zinc sulphate, are obtained by inoculating a solution with a crystal of zinc sulphate, and triclinic crystals of the formula FeSO 4.5H 2 O by inoculating with copper sulphate.
Arsenides, Arsenites, &c. - Several iron arsenides occur as minerals; lolingite, FeAs 2, forms silvery rhombic prisms; mispickel or arsenical pyrites, Fe2AsS2, is an important commercial source of arsenic. A basic ferric arsenite, 4Fe2O3 As2O3.5H 2 O, is obtained as a flocculent brown precipitate by adding an arsenite to ferric acetate, or by shaking freshly prepared ferric hydrate with a solution of arsenious oxide.
Orpiment (auri pigmentum) occurs native in pale yellow rhombic prisms, and can be obtained in the amorphous form by passing a current of sulphuretted hydrogen gas through a solution of arsenious oxide or an arsenite, previously acidified with dilute hydrochloric acid.
As examples of facial holohedra we may notice the small rhombicuboctahedron and rhombic dodecahedron, and the small rhombicosidodecahedron and the semiregular triacontahedron.
It forms rhombic crystals possessing a sweet taste.
It crystallizes in yellow rhombic prisms, and is readily soluble in water, the solution having a bitter taste and an alkaline reaction.
They form rhombic crystals of a red or brown red colour and are readily decomposed by warm water, with formation of the bichromate.
The form of David Mitchell's Six-way Brick is a rhombic dodecahedron from which twelve small rhombic pyramids have been removed.
The triply periodic structure is generated by reflections in the faces of the rhombic dodecahedron.
The form of David Mitchell's Six-way Brick is a rhombic dodecahedron from which twelve small rhombic dodecahedron from which twelve small rhombic pyramids have been removed.
The bisphenoids (the hemihedral forms of the tetragonal and rhombic bipyramids)., and the trigonal pyramid of the hexagonal system, are examples of non-regular tetrahedra (see Crystallography).
This holds for benzene and phenol, and is supported by the observations of Gossner on [1.3.5] trinitrobenzene and picric acid (1.3.5-trinitro, 2 oxybenzene); these last two substances assume rhombic forms, and picric acid differs from trinitrobenzene in having w considerably greater, with x and slightly less.
Rhombic crystals on a crust of tiny calcite crystals covering basalt matrix.
The module can be varied to produce a large number of related rhombic polyhedra and polyhedral combinations.
Ernest commands attention, furiously twisting a soaked beer mat into rhombic shapes.
Most of the HF aerials post-war were rhombic patterns.