IN THE BOTTLE

Keep a coil of copper wire (prepared by winding copper wire round a glass tube) or a little silver powder in the bottle, which should be of brown or amber glass the methyl iodide will remain colourless indefinitely. Ethyl iodide may sometimes give more satis factory results. 

DMSO - Dimethylsulphoxide is a very common solvent with a freezing point of 20 degrees. When you buy this stuff it will be crystallised in the bottle. To melt, all you need to do is place the bottle in a bowl of hot water for 30 minutes - simple. If you re lucky enough to live somewhere warm it may already be liquid, where I live, no chance. When you open the bottle you will notice that this stuff smells a bit farty, don t worry too much, it doesn t get that bad. 500ml straight into the reaction flask and start the stirrer. 

Cuprous chloride, acid (for gas analysis, absorption of CO) cover the bottom of a 2-liter bottle with a layer of copper oxide % inch deep, and place a bundle of copper wire an inch thick in the bottle so that it extends from the top to the bottom. Fill the bottle with HCl (sp. gr. 1.10). The bottle is shaken occasionally, and when the solution is colorless or nearly so, it is poured into half-liter bottles containing copper wire. The large bottle may be filled with hydrochloric acid, and by adding the oxide or wire when either is exhausted, a constant supply of the reagent is available. 

Stannous chloride, SnClj THjO—0.5N 56 g per liter. The water should be acid with HCl and some metallic tin should be kept in the bottle. 

In 1997 it was estimated that global production of PET was about 16.7 X 10 t.p.a., of which 12 million tonnes was used in textiles, 2 million tonnes for audio and video film (with a small quantity for technical mouldings) and 3 million tonnes for packaging, particularly bottles. The tremendous growth in the bottles market from zero in the late 1970s to 1.5 million tonnes in the USA alone in 1998 is, in consumption terms, one of the most spectacular examples of growth in plastics materials in recent times and will be considered later in this section. 

A cylindrical polypropylene bottle is used to store a liquid under pressure. It is designed with a 4 mm skirt around the base so that it will continue to stand upright when the base bulges under pressure. If the diameter of the bottle is 64 mm and it has a uniform wall thickness of 2.5 mm, estimate the maximum internal pressure which can be used if the container must not rock on its base after one year. Calculate also the diameter change which would occur in the bottle after one year under pressure. 

If the diameter of the bottle is 160 mm, calculate the hoop and axial strains in the bottle wall when an internal pressure of 200 kN/m is applied. Calculate also the stresses in the individual layers. 

The most convenient setup for hydrogenation on an intermediate synthetic scale is the Parr low-pressure shaker-type apparatus (Fig. A3.9), in which variable pressures of from 1 to 5 atmospheres (60 psi) may be safely employed. The compound to be hydrogenated (approx. 100 g) is dissolved or suspended in 200 ml of a suitable solvent in a heavy-walled 500-ml bottle. The bottle is placed in the apparatus and clamped in place inside the protective mesh. The flask is briefly evacuated, then filled with hydrogen to the desired pressure. The reaction is initiated by starting the shaker, and the course of the reaction is easily followed by observing the drop in pressure in the bottle and... 

It is essential that great care should be taken that the temperature be accurately determined when taking the specific gravity. The bottle filled with oil takes some time to assume the exact temperature of the water in which it is immersed, especially if these differ much at first. Hence it is always advisable not to depend only on an observation of the temperature of the water, but to use a very small bulbed thermometer with which the kctual temperature of the oil itself in the bottle can be taken. Specific gravities are usually expressed as the ratio of the weight of a volume of the oil to that of an equal volume of water, both at 60° P .,... 

It is rarely that any greater degree of accuracy than that attained in the above methods is required. If, however, scientific accuracy is necessary in specific gravity determinations, the usual standard of comparison, at whatever temperature the determination may be made, is water at its maximum density temperature, namely 4°. If no correction is made for the weight of the air contained in the bottle or tube, accuracy to the fourth place of decimals is ensured by reducing the observed weighings to vacuum weighings. This can be done by the equation—... 

An Alka-Seltzer tablet gives off carbon dioxide when dissolved in aqueous solution. The gas is used to drive hydrogen sulfide out of drilling fluid samples. The H S then reacts with lead acetate paper in the bottle cap. The degree of discoloration is related to hydrogen sulfide concentrations. 

It is then hottled as quickly as possible, before the gas has time to bubble out again. Once it is sealed in the bottle, cooling is not needed for storage. 

A squeeze bottle can be simply made from a 500-ml. narrowmouthed polyethylene bottle and polyethylene tubing. Holes in the bottle cap and shoulder are made with a sharp cork borer of the appropriate size to ensure a tight fit with the inserted tubing. 

The brown oxide is a heavy granular powder which settles to the bottom of the solution in the bottle in which the reduction is carried out (p. 10). It must be reduced to platinum black before it becomes a catalyst for the reduction. When the hydrogen is admitted and the bottle shaken the brown oxide becomes black and whips up into a fine suspension. The time necessary for the change of the oxide to platinum black is called the lag. The time of lag varies usually from several seconds to two or three minutes, depending upon the conditions under which... 

Polythene wash bottles are sometimes charged with wash liquids other than water. Attention must be drawn to the fact that the components of some wash solutions may pass into the polythene and may be released into the space in the bottle when it is set aside repeated fillings and rinsings may be required to remove the chemicals from the bottle. It is safer to label the wash bottle and to reserve it for the special wash liquid. Such wash solutions include a weakly acid solution saturated with hydrogen sulphide, dilute aqueous ammonia, saturated bromine water, and dilute nitric acid. 

If the initial reaction is allowed to proceed too rapidly, considerable pressure may be developed in the bottles. As a safeguard against explosions it is advisable to enclose the bottles in wire mesh shields. 

States that the dropper should be put back in the bottle immediately after use. 

Self-Test 4.17B The properties of carbon dioxide gas are well known in the bottled beverage industry. In an industrial process, a tank of volume 100. I. at 20.°C contains 20. mol C02. Use the data in Table 4.5 and the van der Waals equation to estimate the pressure in the tank. 

You find a bottle of a pure silver halide that could be AgCl or Agl. Develop a simple chemical test that would allow you to distinguish which compound was in the bottle. 

An old bottle labeled Standardized 6.0 m NaOH was found at the back of a shelf in the stockroom. Over time, some of the NaOH had reacted with the glass and the solution was no longer 6.0 M. To determine its purity, 5.0 mL of the solution was diluted to 100. mL and titrated to the stoichiometric point with 11.8 mL of 2.05 M HCl(aq). What is the molarity of the sodium hydroxide solution in the bottle ... 

Ground surfaces are often found to be jammed together. If the parts are robust, a sharp tap will often release them. A glass stopper stuck in a bottle is often released by tapping with another glass stopper, or something solid. When the substance in the bottle has cemented the stopper in position, the joint may be put in a suitable solvent. Frozen surfaces are often more easily released after the joint has been immersed in a deter nt solution for some time. 

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