A. SMITS and C. A. LOBRY DE BRUYN: "On the Periodic Passivity of Iron. II" 



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Sealed- in iron electrode 1.5 cm. long, of a diameter of 3 mm. Solution 

 contains per Liter 0.72 gr. mol. FeS04 ± 0.01 4 gr. mol. FeCl.,. Potential 

 measured halfway the height. Current density 28— 33 milli-ampère;cm=. 

 I iieriod 6.15 seconds. Difference of the extreme values + 1.7 Volt. 



Fig. ^ü. Iron electrode 5.3 cm. long of a di: 

 as in the e.\periment in fig. 1. Pote 

 Current density 38 — 43 milli-ampère 



ealed in. Solution 

 . from the bottom. 



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Electrode, solution and arrangement siphon for potential measuri 

 ment as in e.\per!ment in fig. 1, Current density 25—30 mill 

 ampere cm-, 1 period 7.8 seconds. 



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Fig, 5. Iron electrode 5,1 cm, long of a diam. Fig, 5a, Electrode, solution and 



of3 mm, not sealed in. Potential measured arrangement siphon for potential 



halfway the height. Current density 30-34 measurement as in fig. 5, Current 



milli-ampère/cm^, 1 period 2,2 seconds, density 28-32 milli-ampère/cm-. 



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Electrode 1,4 ci 

 as in the e.vperi 



long, of a diameter of 3 i 

 in fig, 1, Potential I 



electrode. Curient density 32—36 milli-an 



1., not sealed in, solution 

 ured at the bottom of the 

 e cm-'. 1 period 5.25 sec. 



Fig. 6. Electrode and solution as in fig, 5, Potential measured 1 mm, under the 

 liquid level. Current density 47—53,5 milli-ampère/cm-, 1 period 

 3.65 seconds. 



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F.g, 4. Electrode 5.1 cm. long of a diameter of 3 mm., not sealed in. 

 Solution as in the experimem in fig, 1. Potential measured 1mm. 

 from the bottom. Current density 24-39 milli-ampère cm-'. 1 period 

 i 5,1 seconds. 



Fig, 7, Electrode ± 60 cm. long of a diameter of 3 mm, electrode spirally wound 

 in 5 windings. Potential measured at the second winding from the top. 

 Strength of the current regularly periodical at + 0.5 ampère. 



