Cathodes silver chloride

Jones and Bradshaw [J. Am, Chem, Soc. 54, 138 (1932)] passed a current of approximately 0.025 amp. for 8 hours through a solution of lithium chloride, using a silver anode and a silver chloride cathode 0.73936 g. of silver was deposited in a coulometer. The original electrolyte contained 0.43124 g. of lithium chloride per 100 g. of water, and after electrolysis the anode portion, weighing 128.615 g., contained 0.35941 g. of salt per 100 g. water, while the cathode portion, weighing 123.074 g., contained 0.50797 g. of salt per 100 g. of water. Calculate the transference number of the chloride ion from the separate data for anode and cathode solutions. 

A solution, 100 g. of which contained 2.9359 g. of sodium chloride and 0.58599 g. urea, was electrolyzed with a silver anode and a silver chloride cathode after the passage of current which resulted in the deposition of 4.5025 g. of silver in a coulometer, Taylor and Sawyer [/. Chem. Soc. 2095 (1929)] found 141.984 g. of anode solution to contain 3.2871 g. sodium chloride and 0.84277 g. urea, whereas 57.712 g. of cathode solution contained 2.5775 g. sodium chloride and 0.32872 g. urea. Calculate the true and apparent transference numbers of the ions of sodium chloride in the experimental solution. 

The silver chloride cathode reaction is given by Eq. (8) in reverse that is, silver chloride is reduced to form metallic silver and chloride ion. The silver chloride cathode shares many of the qualities of the silver anode, with some additional desirable traits No electrolyte is depleted by its reaction it is hydrophilic and therefore wetted by the reservoir electrolyte and the insoluble reaction product, metallic silver, is electrically conductive, eliminating problems of polarization or isolation of the redox species. Because of this combination of properties, the operating voltage of silver chloride decreases with use, and the utilization of a silver chloride cathode is nearly 100%. 

To establish a good in vitro/in vivo correlation, the composition and ionic strength of the receptor solution must be adjusted. For fentanyl, the best correlation was obtained with a receptor solution comprised of a 10-fold dilution of modified Dulbecco phosphate-buffered saline (without calcium or magnesium) at pH 7.4. The currents tested in vitro ranged from 0 to 400 pA and were applied to a silver anode and a silver chloride cathode using a constant current power supply. The in vitro data presented in Fig. 5 clearly demonstrate the expected linear dependence of fentanyl delivery on current and the excellent correlation to the in vivo data. 

The polyethylene membrane covered an electrochemical enzymatic biosensor. The construction scheme of the sensor is displayed in Fig. 25. The electrochemical basic electrodes consist of a platinum anode and a silver-silver chloride cathode. A thermally sensitive layer of glucose oxidase was localized directly on the anode surface and was covered by a 30-pm-thick hydrophobic polyethylene membrane. The biosensor for the detection of the glucose concentration is based on an enzyme (glucose oxidase)-cat-alyzed reaction of the analyte (glucose) and the subsequent electrochemical detection of a reaction product (electron current). A stoichiometric surplus of the coreactant oxygen has to be guaranteed. This is realized by the polyethylene membrane (membrane with analyte door ) controlling the glu-... 

H202 is monitored at +650 mV applied potential vs. a silver/silver chloride cathode. Using the two enzyme biosensors results in an increase in the reliability because of the increase of selectivity and reproducibility of the results. 

Potassium chloride was electrolysed between a silver anode and a silver/silver chloride cathode at 25 °C (Macinnes and Dole, J. Amer. Chem. Soc. 1931, 53, 1361). In the case of a 0.05 M solution, 0.3216 g silver were deposited in a silver coulometer in series with the cell during the passage of current, and afterwards analj es were carried out on five sections of the potassium chloride solution located in the cell as follows... 

The following data (Longsworth, J. Amer. Chem. Soc. 1932, 54, 2745) refer to the movement of a rising boundary between solutions of sodium and cadmium chlorides the lower electrode was a cadmium anode and the upper a silver/silver chloride cathode. The temperature was 25 C, the current was maintained constant at 16.00 x 10 int. A, the cross-sectional area of the tube was 0.1115 cm and the concentration of the sodium chloride 0.02 molel-. Table 1 gives some corresponding readings of the time t and the distance of traverse of the boundary x. 

Nonsilver cathodes are usually prismatic in shape and are fiat. Silver chloride cathodes are used fiat and corrugated in many configurations. 

Terminations. For silver chloride cathodes the lead is soldered directly to silver foil, which has been heat-sealed to one surface of the silver chloride. Leads are soldered directly to the collector grid of nonsilver cathodes or soldered to a piece of copper foil, which has been stapled to the collector grid. 

This material can be used only in seawater or similar chloride-containing electrolytes. This is because the passivation of the silver at discontinuities in the platinum is dependent upon the formation of a film of silver chloride, the low solubility of which, in seawater, inhibits corrosion of the silver. This anode, consisting of Pt-lOPd on Ag, was tried as a substitute for rapidly consumed aluminium, for use as a trailing wire anode for the cathodic protection of ships hulls, and has been operated at current densities as high as 1 900 AmHowever, the use of trailing anodes has been found inconvenient with regard to ships manoeuvrability. 

Conversion of substituted nitrobenzenes to the arylhydroxylamine is easily achieved by reduction in neutral or slightly acid solution. In the first classical experiments, Haber [35] used a platinum cathode and ammonia ammonium chloride buffer and die process was improved by Brand [57] using either a nickel or silvered copper cathode in an acetate buffer. The hydroxylamine can also be obtained from reduction in dilute sulphuric acid provided tire temperature is kept below 15° C to suppress furtlier reduction [58]. This electrochemical route to arylhydroxylamines due to Brand is superior to the chemical reduction using zinc dust and ammonium chloride solution. The latter process is known to give variable yields depending on... 

A sensor for dissolved oxygen is based on a similar principle as the C02, employing a gas-permeable membrane which selectively allows diffusion of oxygen into a thin layer of—usually—phosphate buffer. However, this sensor typically operates in amperometric mode, i.e., the signal is generated by reduction of oxygen at the platinum or gold cathode with silver chloride used as the anode. 

Current was delivered to the membranes through silver/silver chloride (Ag/AgCl) electrodes for iontophoresis, whereas stainless steel electrodes were employed for electroporation studies. Of the two model compounds, L-glutamic acid carries a net negative charge of 1 at pH 7.4, whereas estradiol is nonionized. Hence, they were delivered under the cathode and anode, respectively. 

Nowadays, the most commonly used DO electrode is the polarographic that employs an electrochemical method, through the reduction of molecular oxygen at the platinum electrode (cathode) generating electrons for the silver oxidation at the silver/silver chloride electrode (anode). In this type of sensor, it is necessary to impose an external voltage and the resulting current is measured and converted into dissolved oxygen concen-... 

Fig. 6. Cell for macroscale electrolysis at controlled potential consisting of a 2-liter beaker covered with a glass plate G, containing holes for a silver/silver chloride referenoe electrode R, the anode compartment, a cooling coil S, a thermometer, an inlet for nitrogen, and one for withdrawing of samples. The mercury cathode C has an area of 125 cm2. The diaphragm D consists of two porous clay cylinders separated by agar containing KC1. The anolyte (15% aqueous NaOH) is continuously renewed through T. Anode A is of stainless steel. From Iversen and Lund.55...

Silvei Silver Chloride Electrodes. Silver silver chloride electrodes may be made from thin sheet silver of high purity, but it is perhaps better to plate silver onto a clean square of platinum sheet or screen. This is made the cathode, and the anode is a strip of very pure sheet silver (at least 99.95 percent pure) in a plating bath containing 41 g silver cyanide, 40 g potassium cyanide, 11 g potassium hydroxide, and 62 g potassium carbonate... 

Macinnes and Dole [/. Am, Chem, Soc, 53, 1357 (1931)] electrolyzed a 0.5 N solution of potassium chloride, containing 3.6540 g. of salt per 100 g. solution, at 25 using an anode of silver and a cathode of silver coated with silver chloride. After the passage of a current of about 0.018 amp. for approximately 26 hours, 1.9768 g. of silver were deposited in a coulometer in the circuit and on analysis the 119.48 g. of anode solution were found to contain 3.1151 g. potassium chloride per 100 g. solution, while the 122.93 g. of cathode solution contained 4.1786 g. of salt per 100 g. Calculate the values of the transference number of the potassium ion obtained from the anode and cathode solutions, respectively. 

Lingane found that (14-24) is obeyed in the deposition of copper onto a platinum cathode from a tartrate solution and in the deposition of lead and reduction of picric acid at a mercury cathode. Lingane and Small found the same type of relation in the anodic formation of silver chloride. 

Radiometer pOz electrode, type E 5046 consists of a platinum cathode (20 /am diameter) and silver-silver chloride reference electrode placed in an electrochemical solution behind a 20 /am thick polypropylene membrane. A polarizing voltage of about 650 mV is applied. The polarographic current is about 10 " A per mm Hg of oxygen tension at 38°C. Zero current is lower than 10 A, response time less than 60 sec at 38°C 99% of full deflection. The PO2 electrode is used with the pH-Meter 27 GM or the Astrup Micro-Equipment, in conjunction with the Oxygen Monitor. The scale can be calibrated to the range 0-100 mm Hg p02. Thermostated cells provide measurements at constant temperature of volumes down to 70 /al. The small volume makes this cell useful to measure the PO2 of capillary blood. The cell is supplied with accessories for blood sampling. 

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