Coulometer sodium

If minute quantities of electricity are to be measured the electrolytic gas coulometer is recommended in this case a 15 per cent solution of sodium hydroxide is used as electrolyte while the electrodes are of platinum or nickel. Both the hydrogen and the oxygen escaping from the closed electrolytic cell... 

The electrolytic gas coulometer is useful for the approximate measurement of small quantities of electricity the total volume of hydrogen and oxygen liberated in the electrolysis of an aqueous solution of sulfuric acid or of sodium, potassium or barium hydroxide can be measured, and from this the quantity of electricity passed can be estimated. If the electrolyte is dilute acid it is necessary to employ platinum electrodes,... 

A current of 0.050 amp. was passed through a silver titration coulometer, and at the conclusion 23 8 cc. of 0.1 n sodium chloride solution were required to titrate the silver dissolved from the anode. How long was the current flowing ... 

In an experiment on the electrolytic reduction of sodium nitrate solution, Muller and Weber [Z. Elektrochem., 9, 955 (1903)] obtained 0.0495 g. of sodium nitrite, 0.0173 g. ammonia and 695 cc. of hydrogen at S.T.P., while 2.27 g. of copper were deposited in a coulometer. Evaluate the current efficiency for each of the three products. 

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. 

A constant-potential coulometric determination of copper is being done using a mercury-pool cathode and a water coulometer. A volume of 32.14 ml of hydrogen-oxygen mixture is obtained. The temperature of the gas is 24.0°C and the barometric pressure in the room is 752.0 mm of mercury. The water vapor pressure above the 0.1 M sodium sulfate solution in the coulometer is as follows ... 

Another chemical coulometer depends on the production of a gas. Classically, this was the combined H2 and O2 from electrolysis of water containing an indifferent electrolyte such as sodium sulfate. This is fairly sensitive, but involves the inconvenient measurement of a gas volume, which must be corrected to standard conditions of temperature and pressure. The apparatus for collecting and measuring the mixed gases was called a "voltameter," but T. W. Richards (16), noting the possible confusion with "voltmeter," coined the name "coulometer."... 

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