145 



From tlie foregoing experiments the following conclusions appear jus- 

 tifiable. First, nascent liydrogen dlitaiued from varying sources and in con- 

 tact witli different snbstances lias about the same reducing power. And. 

 second, gaseous hydrogen in contact with iuetals used to make nascent 

 hydrogen is not made more active l)y that c<intact. If these conclusions 

 are justifiable the argument upon which tlie "contact" explanation is 

 based becomes greatly weakent'd. And it becomes still weaker when the 

 first part of the work of Tranbe. described above, is considered. For if 

 contact with palladium is the only cause of llie activity of nascent hydro- 

 gen there is i.o reason why tlie same substance should not have formed at 

 the two poles. It remains to show that the activity of ai)sorbed hydrogen is 

 not due to contact action. 



Much work lias been done in investigating the phenomena of absorp- 

 tion of gases by metals. From the vtjlume of gris absorbed by different 

 metals, as platinum, silver and nickel, Sieverts (Zeit. fur Phys. Chem. LX, 

 129 and LXVIII, 11.1) concluded that the absorbed element was in the 

 atomic state. Richardson (Phil. Mag. \l . 2C,i\ and VIII. 1), in his studies 

 on the diffusion of gases through metals came to the same conclusion, say- 

 ing "This result can be exjjlained by supposing that the hydrogen is dis- 

 sociated and that the dissociated atoms ]iass freely through the platinum." 

 Gladstone and Trilie in their work on "The Actii»n of Substances on Nas- 

 cent and Occluded Hydrogen" (C. S. .Iouiti. INTO. 170, Trans.) say "Among 

 other results of this investigation we may i-laim to have established still 

 more fully the close likeness of character and therefore of condition be- 

 tw^eeu hydrogen usually denominated nascent and hydrogen occluded by 

 metals," Also P.ain in liis work on the alisorption of hydrogen by carbon 

 (Zeit. fur Phys. Chem. LXVIII. 471 ) concludes that the absorbed hydro- 

 gen is in tlie atomic state. If these conclusions are justified the activity of 

 al)sorbed hydrogen nee<I not be banger considered as due to "contact" 

 action. But if it still be found that contact does modify the activity of ele- 

 ments is it not a condition of chemical activity or a means of altering the 

 velocity of a chemical change rather than an explanation? Does not the 

 question remain, "Why. and in what manner they do so? ^Manganese diox- 

 ide accelerates the decomi)ositioii of potassium chlorate, but this fact does 

 not thrown any light on the mechanism of the reaction nor does it explain 

 why the oxygen at the instant of .separation is a better oxidizing agent 

 than ordinary oxygen at tb.e same temperature. Heat is a necessary condi- 



10—33213 



