Adaptors

Experimental Determination of Boiling-point. Unless only minute quantities of the liquid are available cj. p. 60), the boiling-point is usually determined by simple distillation. For this purpose, the apparatus shown in Fig. 2 is assembled. A distillation flask A of suitable size is fitted to a water-condenser B, the water supply of which is arranged as show-n. An adaptor C is sometimes fitted in turn to the condenser, so that the distillate... 

The above units can when required be fitted into the neck of a flask by adaptors such as Fig. 22(K) and Fig. 22(L). 

Fig. 23(B) shows a modification of the reflux assembly to allow a gas to be passed through the boiling liquid cf. Fischer-Speier esterification, p. 104). The inlet-tube A fits into a three-necked adaptor shown in Fig. 22(J). The stopper B can be replaced by a dropping-funnel, etc.

Fig. 23(D) shows a simple distillation apparatus with an adaptor fitted to the lower end of the condenser. This apparatus can also be used for the recovery of solvents, or for the concentration of a solution with collection of the distilled solvent.

Fig. 23(E) shows a distillation assembly particularly useful for distilling ether from an ethereal extract. When all the ether has distilled over, the drop-ping-funnel may be replaced by a thermometer for distillation of the residual liquid the adaptor A and the receiver B can then be replaced by the simple adaptor shown in Fig. 23(D) and a flask or bottle of suitable size.

Fit a 500 ml. bolt-head flask F with a well-fitting cork which is free from flaws, and which carries a dropping-funnel D and a delivery tube (or knee-tube ) T, the latter being connected to a water-condenser C (Fig. 52). Attach an adaptor A to the lower end of the condenser. (Alternatively, use a ground-glass flask (Fig. 22(a), p. 43) with a distillation-head (Fig. 22(F)) the dropping-funnel can be fitted into the distillation-head, the side-arm of which is connected to a condenser as in Fig. 23(0), p. 45.)... 

Assemble the apparatus shown in Fig. 6o. A is a 500 ml. bolt-head flask connected by a knee-tube B to a water-condenser C, to the lower end of which is fitted the adaptor D. In view of the low boiling-point of the ethyl bromide, it is essential that the various portions of the apparatus are connected together by well-bored, tightly fitting corks. (For this reason, the apparatus shown in Fig. 23(0), p. 45, is preferable.)... 

Arrange the adaptor D so that the end dips below the surface of about 50 ml. of water contained in a small conical flask, or beaker, which is in turn surrounded by a mixture of ice and water. Place 37 (30 g-) of ethanol and 25 ml. of water in the flask A, and... 

A 1500 ml. flask is fitted (preferably by means of a three-necked adaptor) with a rubber-sleeved or mercury-sealed stirrer (Fig. 20, p. 39), a reflux water-condenser, and a dropping-funnel cf. Fig. 23(c), p. 45, in which only a two-necked adaptor is shown or Fig. 23(G)). The dried zinc powder (20 g.) is placed in the flask, and a solution of 28 ml. of ethyl bromoacetate and 32 ml. of benzaldehyde in 40 ml. of dry benzene containing 5 ml. of dry ether is placed in the dropping-funnel. Approximately 10 ml. of this solution is run on to the zinc powder, and the mixture allowed to remain unstirred until (usually within a few minutes) a vigorous reaction occurs. (If no reaction occurs, warm the mixture on the water-bath until the reaction starts.) The stirrer is now started, and the rest of the solution allowed to run in drop-wise over a period of about 30 minutes so that the initial reaction is steadily maintained. The flask is then heated on a water-bath for 30 minutes with continuous stirring, and is then cooled in an ice-water bath. The well-stirred product is then hydrolysed by the addition of 120 ml. of 10% sulphuric acid. The mixture is transferred to a separating-funnel, the lower aqueous layer discarded, and the upper benzene layer then... 

Attention is directed to the fact that ether is highly inflammable and also extremely volatile (b.p. 35°), and great care should be taken that there is no naked flame in the vicinity of the liquid (see Section 11,14). Under no circumstances should ether be distilled over a bare flame, but always from a steam bath or an electrically-heated water bath (Fig.//, 5,1), and with a highly efficient double surface condenser. In the author s laboratory a special lead-covered bench is set aside for distillations with ether and other inflammable solvents. The author s ether still consists of an electrically-heated water bath (Fig. 11, 5, 1), fitted with the usual concentric copper rings two 10-inch double surface condensers (Davies type) are suitably supported on stands with heavy iron bases, and a bent adaptor is fitted to the second condenser furthermost from the water bath. The flask containing the ethereal solution is supported on the water bath, a short fractionating column or a simple bent still head is fitted into the neck of the flask, and the stUl head is connected to the condensers by a cork the recovered ether is collected in a vessel of appropriate size. 

The best replacement for borosilicate glassware is stainless steel. Stainless steel takes the heat, won t break, and, most importantly, is about as resistant to chemical degradation as the chemist can hope to find. For those items that won t be subjected to direct heat there can be some steel/metal or steel/plastic hybrids. In figure 3 is shown how flasks of any size can be made with two stainless steel mixing bowls welded together. Also shown is the vacuum adaptor and condenser. For the condenser only the inner pipe need be steel. The outside pipe can be copper or something. As for the other components of a distillation set up, well, they are made just as they look. 

This adaptor consisted of two 24/40 joints connected with Gooch tubing. 

When there is a choice, design for no flashing. When there is no choice, locate the valve to flash into a vessel if possible. If flashing or cavitation cannot be avoided, select hardw are that can withstand these severe conditions. The dowmstream line will have to be sized for tw o phase flow. It is suggested to use a long conical adaptor from the control valve to the downstream line. 

Small protein modules form adaptors for a signaling network... 

Die-adaptor Piece of an extrusion die that serves to hold die block. 

Fortunately in this case the two materials did not react. People who have emptied acid into alkali tanks have been less fortunate. A plant received caustic soda in tank cars and acid in tank trucks. One day a load of caustic soda andved in a tank truck. It was labeled Caustic Soda, the delivery papers said it was caustic soda, and the hose connections were unusual. But the operators had a mind-set (see Section 3.3.5) that anything in a tank truck was acid, and they spent two hours making an adaptor to enable them to pump the contents of the tank truck into the acid tank. 

Many suppliers of liquefied gases state that they use different hose connections for liquid oxygen and liquid nitrogen so mistakes cannot arise. However, mistakes have occurred, possibly because of the well-known tendency of operators to acquire adaptors. 

Today it is usually harder than in the early days of computer control for operators to interfere with the software, override interlocks, or type in coiTect readings. However, many operators acquire keys or passw ords that they should not have, in much the same way as operators have always unofficially acquired and secreted an assortment of tools and adaptors. On one plant an interlock was found to be illegally blocked the password had been disclosed to 40 people, all of whom denied responsi-aility (see Section 14.5 d). 

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