Properties of Sulphur

Rhombic Sulphur. Pour 4-5 ml of chloroform into a dry test tube in a fume cupboard ) and spill in a sulphur powder in small portions, shaking the contents of the tube, until a saturated solution forms. Filter the solution into a porcelain bowl (do not wet the filter with water, why ), cover it with a glass, and let it stand in the fume cupboard for slow evaporation. Put a drop of the solution on a slide, cover it with a cover glass, and observe under a microscope how the crystals grow. Draw the sulphur crystals. 

Monoclinic Sulphur. Fill a small porcelain or chamotte crucible with sulphur, and slowly melt it. The melt should occupy at least half of the crucible. Cool the latter until a crystalline crust forms. When the crust almost covers the melt, rapidly pour out the remaining molten sulphur into a beaker of water. Examine the crystals formed with a magnifying glass and draw them. 

Dissolve two or three of the crystals in chloroform on a watch glass, and after evaporation of the solvent, examine the shape of the newly formed crystals. What structure of the molecules corresponds to the obtained sulphur modifications  

Changes in Sulphur When Heated. Half fill a test tube with pieces of sulphur and, while holding it in your hand with the aid of forceps, slowly heat it in the flame of a burner. Watch the melting and the subsequent changes in the colour and viscosity of the sulphur. Explain the phenomena that occurred. 

Preparation of Plastic Sulphur. Heat sulphur until it boils and pour it out in a thin stream into a crystallizer with cold water. Extract the solid substance from the water and dry it between sheets of filter paper. Test the ductility of the sulphur and its solubility in chloroform. Keep part of the sulphur for the next lesson and again study its physical properties. What molecules does plastic sulphur consist of  

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The current state-of-the-art has significantly advanced the performance properties of sulphur concrete to a point where it is commercially acceptable. However there still are limitations on the durability of the product in extreme temperature regimes. 

Shrive, N.G., Gillott, J.E., Jordaan, I.J., Loov, R.E., Potential Properties of Sulphur Concretes, American Chemical Society Meeting, Atlanta (1981) (This volume)... 

In an earlier state of the art report (1) various properties of sulphur concretes were outlined. In the last few years, researchers have concentrated on the topics of durability (moist environment, biological and chemical attack, cycles of freezing and thawing), stress-strain behaviour and mix proportioning. 

Properties of Sulphuric Acid. (Perform the experiments in a fume cupboard ) Interaction of Concentrated Sulphuric Acid with Water. Pour 10-15 ml of water into a beaker, measure its temperature, and without extracting the thermometer, add 2 ml of a 96% solution of sulphuric acid. Record the thermometer readings. In what sequence must water and concentrated sulphuric acid be poured together to prepare solutions of various concentrations ... 

Prepare 2-3 ml of a sulphuric acid solution (1 1). Wet the tip of a glass rod with this solution and make an inscription on a sheet of white paper. Carefully heat the paper to dry it. What happens What properties of sulphuric acid do the above experiments indicate ... 

Compare the physical and chemical properties of sulphurous, selenous, and tellurous acids (see Appendix 1). 

More recently attention has been paid to the problem of the explosive properties of sulphur dust suspended in air. This is of great importance to work with explosives in sulphur mines. 

Water dissolves about thirty-seven times its volume of this gas the solution possesses the properties of sulphurous acid in a vety high degree, and bleaches vegetal colors with great power when kept for some lime it gradually absorbs oxygen, and the sulphurous becomes converted into sulphuric acid. 

As far as all the useful properties of sulphurous acid are concerned, they may be studied from its solution in water, this liquid taking up, at mean temperature, thirty-three times its hulk of the gas. 

Sulphur is applied, commonly in the powdered form or as /lowers of sulphur, to medicinal purposes, and also agriculturally as a dust or dressing to check fungoid diseases of certain plants, ( specially the vine.5 The toxic properties of sulphur have not been fully elucidated and are variously ascribed to reduction to hydrogen sulphide, oxidation to polythionic acids, or to the vapour of the element itself, produced by slow vaporisation.8 If adsorbed pcntathionic acid be removed from... 

Formation.—Sulphur dioxide imparts to water acidic properties, owing to the formation of an unstable sulphurous acid the chemical properties of moist or dissolved sulphur dioxide are therefore very largely the properties of sulphurous acid. 

Berthoud, J. Chim. phys., 1923, 20, 77 Helv. Chim. Acta, 1922, 5, 513. Other physical properties of sulphur trioxide are also given. 

Physical Properties of Sulphuric Acid.—The pure product obtained by evaporation or distillation whether of a dilute or a fuming acid contains as a maximum approximately 98-4 per cent, of H2S04, the actual figure varying slightly with the pressure.7 At extremely low... 

Occurrence, Extraction, Refining, Applications—The Allotropy of Sulphur Changes in tho Vaporous State, Allotropy in tho Liquid. State, Allotropy in the Solid Stato, Crystalline Forms of Sulphur, Amorphous Sulphur— Colloidal Sulphur—General Physical Properties of Sulphur—Chemical Propertius—Valency—Atomic Weight—Detection and Estimation. 

Steele, H.M., and Hamill, P. (1990) Effects of temperature and humidity on the growth and optical properties of sulphuric arid-water droplets in the stratosphere, J. Aerosol Sci, 12,517-528. 

In recent years the intensive study of sulphur compounds, sponsored by several oil companies43, has led to a collection of physical data on many of these compounds, which enables us to predict several properties of sulphur compounds not yet investigated44 45. 

There have been a considerable number of papers reporting the properties of sulphur-resistant methanation catalysts, i.e., catalysts which can operate successfully in significant partial pressures of H2S. Most of these report work using catalysts containing vanadium, molybdenum, and such metals. However, attempts have been made to find nickel-based catalysts containing suitable additives to allow them to operate in such atmospheres. For example, Bartholomew and Uken115 have compared the deactivation behaviour of a range of nickel catalysts in 10 p.p.m. H2S. They found that nickel boride catalysts and Raney nickel materials deactivated more slowly than did unsupported nickel and alumina-supported nickel. They attributed this improvement to two factors ... 

Investigation of the electronic properties of sulphur-containing molecules... 

Within the last two decades, significant progress has been achieved in the theoretical computation of NMR spectroscopic parameters,110 particularly of nuclear screening constants. Theoretical calculations of 33S NMR parameters have received a certain attention for two main reasons (i) they can help in identifying and elucidating the structural properties of sulphur-containing molecules, and (ii) they can provide important information on the electron distribution and bonding situation around the sulphur atom. 

The nature and property of sulphur of some samples was measured with a XPS, the results are given in Table 4. 

Sulphur isotopes (32,33,34,36S) fractionate strongly in the earth s crust because (1) the element occurs in different oxidation states with differential preference for heavy isotopes, (2) the existence of volatile and easily soluble compounds favors kinetic separations, and (3) it is involved in biogenic cycles where the oxidation state is easily changed and kinetic processes are important. From theoretical calculations of Bigeleisen (1961) and data on the isotopic properties of sulphur compounds by Sakai (1957, 1968), the amount of S isotope fractionation and its temperature dependence is known. The information on experimental inorganic isotope fractionation in coexisting sulphide minerals which occur naturally was summarized by Thode (1970), who also discussed the application of S isotopes from sulphides for geo thermometry (cf. also Sakai, 1971). Analytical work on all types of sulphur compounds which occur in nature has been reviewed by Nielsen (1973). 

Societe Nationale des Petroles d Aquitaine, Properties of Sulphur Bitumen... 

Purification by Sulphuric Acid. Hot sulphuric acid, 100 per cent concentrated, possesses the property of dissolving all three classes of the nitrotoluenes. Upon cooling such a solution, the trinitrotoluene crystallizes, but the mono- and dinitrotoluenes remain in solution. This property of Sulphuric acid forms the basis of another method of purifying TNT. The solution of the TNT in the sulphmic acid is effected in steam-heated, lead-lined vats. The liquor is then filtered and cooled. The recrystallized TNT must be washed with several changes of water to remove the acid. This method... 

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