Stirring motor

The stirring motor is housed in a polyethylene bag to protect it from acid fumes. 

Fig, 11. Standard equipment for reactions carried out under a nitrogen atmosphere. (A) addition funnel (B) standard threenecked round-bottomed flask (C) water-cooled bearing (D) spark-free stirring motor (E) water-cooled Friederichs condenser (F) nitrogen inlet tee (G) trap for mineral oil inadvertently blown into the system (H) 125-ml. mineral-oil-filled bubbler (I) gas exit. 

The following procedure is carried out in a ventilated hood. Finely powdered dry sodium cyanide (29.4 g., 0.60 mol) and 180 ml. of dimethylformamide (DMF) are placed into a 1-1., three-necked, standard-taper round-bottomed flask equipped with a reflux condenser, dropping funnel, and Hirshberg stirrer connected to a high-speed stirring motor. External cooling is provided by a cold-water or ice-water bath. Carbon disulfide... 

Figure 1. Sketch of the hydrostatic balance densitometer— A) magnetic stirrer (B) glass float (C) stirring motor (D) constant temperature bath (E) nickel thermometer (F) lucite plug (G) sample container (H) nylon wire (1) suspension hook (]) Mettler H20 balance (33)...

Equimolar quantities of dichlor (MW 132.91) and difluor (MW 100.01) are dissolved in methylene dichloride and heated to reflux temperature in a three-necked flask equipped with a reflux head, a stir motor, and a dropper. An equimolar quantity of inopropanol (MW 60.11) is added dropwise with stirring at a rate sufficient to keep the mixture boiling gently. Reflux for one hour after the last of the iMopropanol is added. 

Sealed stirrer with stainless-steel stirring rod and appropriate stirring motor (see Note 2)... 

Place the assembled reaction flask in the water bath, attach the stirring motor, and begin stirring. 

Place 376 ml of deionized water into a 1-liter resin kettle equipped with a sealed stirrer and appropriate stirring motor (see also Note 2 of Experiment 2), reflux condenser, thermometer, and nitrogen inlet tube reaching down to just above the stirrer blade. 

Figure 7-1 Typical setup for a titration. The analyte is contained in the flask, and the titrant is in the buret. The stirring bar is a magnet coated with Teflon, which is inert to most solutions. The bar is spun by a rotating magnet inside the stirring motor. 

Figure 11-5 Autotitrator delivers titrant from the bottle at the back to the beaker of analyte on the stirring motor at the right. Electrodes in the beaker monitor pH or concentrations of specific ions. Volume and pH readings can go directly to the spreadsheet program in a computer. [Brinkman Instruments, Westbury. NY.]...

It is advisable to use more powerful stirring motors than those usually found in the organic laboratory, since the success of the preparation is so largely dependent on the production of a good emulsion. The checkers employed two Lightnin stirrers (Model L mixers) having shafts and blades of Monel metal. 

The rate experiments were carried out in 3.5 liter glass jars covered with a plexiglass lid. Two baffles of 2 cm width extended from the lid to 1 cm from the bottom of the reactor. Agitation was provided by a stirring motor with polyethylene stirrers, and the speed of the motor was controlled with a variac. Three liters of solution without the adsorbent particles was agitated, and allowed to reach equilibrium with the vessel before withdrawing the initial sample for analysis. At time t - 0, a measured quantity of activated carbon was introduced into the reactor and agitated. Samples, 10 ml each were withdrawn periodically, until equilibrium was reached, and analyzed for the solute concentration in the liquid phase. The numerical procedure developed earlier was adjusted to allow for the volume reduction due to the withdrawal of samples at discrete time Intervals. 

To 300 ml. of water contained in a 3-1. Erlenmeyer flask fitted with a stirring motor is added 110 g. of arsenic (III)... 

Toward the end of the acid chloride addition, TEA hydrochloride precipitated, and the solution became quite viscous, making stirring and removal of reaction heat more difficult. Hence, a large stirring paddle and a strong stirring motor (e.g., an air-driven stirrer) were used. 

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