Hydrogen reaction + glass vessels

This is a disproportionation reaction, and is strongly catalysed by light and by a wide variety of materials, including many metals (for example copper and iron) especially if these materials have a large surface area. Some of these can induce explosive decomposition. Pure hydrogen peroxide can be kept in glass vessels in the dark, or in stone jars or in vessels made of pure aluminium with a smooth surface. 

The hydrogenation reactions were carried out in a 100-ml stainless-steel autoclave equipped with a 50-ml glass liner and PTFE cover to provide clean conditions. The reactor was magnetically stirred (n = 1000 min 1). The pressure was held at a constant value by a computerized constant volume - constant pressure equipment (Buchi BPC 9901). By monitoring the pressure inside the vessel and the injected pulses, the hydrogen uptake could be followed. Under standard conditions, 42 2 mg prereduced catalyst, 1.84 mmol substrate, 6.8 imol modifier and 5 ml solvent were used at 10 bar and room temperature. 

Many investigations of the decomposition of hydrogen peroxide involving base catalysis have been made these have been reviewed . The extent to which the surface of glass vessels can control such rates has been emphasised . The rates of the homogeneous reaction have been measured , after scrupulous attention to purification. Then the rate equation is... 

The Wilzbach procedure is a simple method of labelling organic compounds with tritium The substance is exposed to tritium gas in a sealed glass vessel for several days or weeks. During this period, some of the hydrogen atoms of the molecule to be labelled are substituted by H atoms. Chemical side reactions may take place however at the same time, e.g., unsaturated compounds may be partly or completely hydrogenated. Several firms carry out this type of labelhng on request [312]. 

From his friend Priestley, Cavendish orally got the following information On April 18 in 17811 used my electric machine and fired a mixture of common air and hydrogen in a closed thick-glass vessel. It functioned but I don t think that common air and hydrogen can be a substitute for gunpowder. Priestley at this time was obviously working on another problem than studying chemical reactions [9.1]. 

Hydrofluoric and hydrochloric acids can also be prepared by the action of other strong acids on the halides. For example, Priestley first prepared hydrogen chloride this way, and Scheele s attempts to similarly prepare hydrogen fluoride were thwarted only by the subsequent reaction of HF with his glass vessels. However, when bromides and iodides are treated with sulfuric acid, the elements are produced rather than the hydrides. Indeed, this is how Courtois first produced iodine. Note that the mild oxidizing power of sulfuric acid is sufficient to produce iodine from iodides but not fluorine or chlorine from the corresponding halides. Equation (18.10) illustrates this type of reaction for bromine ... 

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