276 



E. L. Nichols — Chemical Behavior of Iron 



resulting solution indicated that in the magnetic field the chem- 

 ical changes were not the same as those produced under other 

 circumstances. 



When the above-mentioned reaction was performed below 

 the critical temperature, it was found that the mere actuation 

 of the magnet, at any time before the last particle of iron was 

 dissolved, was sufficient to modify the reaction. The evolution 

 of nitrous fumes always followed the closing of the circuit, in 

 such cases, and the change in the character of the reaction was 

 indicated by renewed rise of temperature. Curve "e" shows 

 the range of the thermometer during one of these reactions. 

 The change from the unbroken line to the dotted line shows 

 the point at which the magnet was thrown into action. 



Table I gives the observations from which curves a, b, c, d r 

 and e are drawn. The reactions were repeated many times 

 under the various conditions already described, but the varia- 

 tions from the typical results given in the table were not such 

 as to render necessary the publication of all the observations. 



Table I. — Action of aqua-regia upon iron. 





Tempekattjke. 



TIME. 



Tempebatttbe. 



TIME. 



: e 3? 



oat 



OS* 



gS| 



P5 a 



!?^ bio 

 2 5Po 



z ■*-= so 

 c§.S 

 ~of" 



fa" 



P3 a 



- <v,A 



aasn 



O SC = 



33 US 



OS- 



K 



s += he 



*^ °- OS 



OB, 



° a" 



° 2 



03 O 



.2 go 

 3a s 



sc-5 



m 



g"o 



o sea 



E SB 



a Po 

 o 



all 



5 tarS 



03 a 



QUI s 



30 



1 



1 30 



2 



2 30 



3 



3 30 



4 



4 30 



5 



5 30 



6 



6 30 



7 



7 30 



8 



18-90 

 27-30 

 32-40 

 35-60 

 37-50 

 38-45 

 39-10 

 39-45 

 39-57 

 39-60 

 3960 

 39-60 

 39-60 

 39-55 

 39-50 

 39-45 

 39-40 



20 



28 

 33 

 36 

 38 



39 

 40 

 4 

 40 

 40 

 41 

 40 

 40 

 40 

 40 

 40 

 40 



20 

 10 



50 

 80 

 85 

 60 

 30 

 70 

 85 

 97 

 00 

 97 

 90 

 89 

 78 

 62 

 50 



24-70 



31-10 



37-80 



40-90 



42-50 



4320 



43-70 



43-85 



44-00 



44-05 



44-05 



43-95 



43-90 



43-60 



43-85f 



49-4 



502 



24-38 



57-45 

 57-58 

 57-32 

 5700 

 56-75 

 56-37 



19°80 



34-35 



25-70 



3627 



36-55 



36-70 



36-80 



3680 



36-80 



36-70^: 



36-80 



36-70 



3657 



36-45 



42-80 



43-50 



8 m 30 s 



9 



9 30 



10 



10 30 



11 



11 30 



12 



12 30 



13 



13 30 



14 



14 30 



15 



15 30 



16 



39 ? 30 

 39-20 

 39-10 

 39-00 

 38-95 

 38-85 

 38-75 

 38-62 

 38-50 

 38-25 

 38-20 

 38-10 

 38-00 

 3790 

 37-85 

 37-75 



40 ? 40 



40-30 



40-15 



40-00 



39-90* 



40-40 



44-10 



47-00 



47-35 



47-50 



47-37 



47-30 



47-15 



50-40 

 50-40 

 50-30 

 50-10 

 50-00 

 49-80 



.... 



43-80 

 43-70 

 43-00 









* Red fumes appeared. f Red fumes appeared. % Magnet set into action. 



It will be seen that the speed of reaction is greater in the 

 magnetic field than without, and that the heat of chemical union 

 is much greater. The production of nitrous fumes under the 

 influence of the magnet and the yellow color of the resulting 

 solution showed that the reaction was modified in chemical 

 character as well as in intensity. 



