Electronic buret

Nitrtir, n. (-ous) nitride. Cf. Chloriir. Nitrylsaure,/. nitrylic acid (nitrous acid). Niveau, n. level, -flache, /. level surface, -flasche,/. leveling bottle, leveling vessel (as for a gas buret), -rohr, n., -rohre, /. level tube, leveling tube, -stufe, /. (of electrons) energy level. ... 

Electronic devices such as automatic titrators and digital burets may be used in place of the traditional glass buret and manual titration. Such devices provide electronic control over the addition of titrant and thus, with proper calibration, are accurate, high-precision devices. These will be discussed in Section 4.9. 

There are also various devices that are commonly used for titrations in place of the glass burets previously described. A digital buret, for example, is an electronically controlled bottle-top dispenser that delivers 0.01-mL increments from a reagent bottle containing the titrant. There are also automatic titrators, such... 

Philadelphia. PA ] (b) Digital titrator with plastic cartridge containing reagent solution is used for analyses in the field. [Courtesy Hach Co., Loveland, CO] (c) Battery-operated electronic buret with digital readout delivers 0.01-mL increments from a reagent bottle. This device can be used for accurate titrations in the field. [Courtesy Cote-Parmer Co.. Niles. ILJ... 

Safety requires you to think in advance about what you will do never do anything that seems dangerous. Know how to use safety equipment such as goggles, fume hood, lab coat, gloves, emergency shower, eyewash, and fire extinguisher. Chemicals should be stored and used in a manner that minimizes contact of solids, liquids, and vapors with people. Environmentally acceptable disposal procedures should be established in advance for every chemical that you use. Your lab notebook tells what you did and what you observed it should be understandable to other people. It also should allow you to repeat an experiment in the same manner in the future. You should understand the principles of operation of electronic and mechanical balances and treat them as delicate equipment. Buoyancy corrections are required in accurate work. Burets should be read in a reproducible manner and drained slowly for best results. Always interpolate between markings to obtain accuracy one deci-... 

There are numerous automatic titrators that employ potentiometric end-point detection. They usually can automatically record the first or second derivative of the titration curve and read out the end-point volume. The sample is placed in the titration vessel, and the titrant, drawn from a reservoir, is placed in a syringe-driven buret. The volume is digitally read from the displacement of the syringe plunger by the electronic driver. Titrators may also employ photometric detection of indicator color changes. An automatic titrator is shown in Figure 14.7. Automatic titrators make volumetric analyses rapid, reproducible, and convenient. While instrumental methods provide many advantages, classical volumetric analyses are still widely used and are very useful, especially for major constituents, for example, in the pharmaceutical industry. 

For simple titrations the equipment necessary is not particularly sophisticated a thermometer, a buret, and an insulated beaker (or even two Styrofoam cups, one sitting in the other) will do. However, if one wants to measure specific heats or the heat of reaction, better control is required. Modern automated thermometric titrators consist of a constant delivery pump for the titrant, a temperature control system for the titrant, an insulated cell, cahbration circuitry, electronic temperature sensing, and a data processing system. Most modem instraments are totally computerized, so different methods can be programmed and mn unattended. 

Dioxygen is oxidant turnovers measured by O2 uptake using gas burets. In calculating turnovers dioxygen is assumed to be a four-electron oxidant. 

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