Manchester Meuwirs, Vol. hi. (19 12), No. 6. 3 



However, it was observed that at this temperature a 

 trace of ethylene was produced (about i part in i,ooo,coo). 

 As is well known, this will react with hydrogen at lower 

 temperatures, giving methane, which in this case would 

 raise the amount of the latter above the equilibrium value 

 at the temperature of the rod. It was found that methane 

 is exceedingly stable at 1200", and could not be decom- 

 posed to the equilibrium value, in absence of a catalyst, 

 even after a period of several days. 



Data obtained from the above experiments have 

 shown that the ;^hole of the methane obtained at 1200' 

 could not have arisen from this ethylene, but that a con- 

 siderable part of til is tjuantit}- was probably derived in 

 this way, and the value did not represent the true 

 equilibrium. 



In the case of methane, which is found according to 

 the equation C-f 2H., = CH4, the criterion of a true 

 equilibrium is that the following conditions shall be 

 satisfied : 



(i) At any particular temperature a constant value 

 is given for the ratio of methane to hydrogen. 



(2) This same value for the ratio of these gases results 

 when an e.xcess of methane is taken in the first place and 

 allowed to decompose. 



(3) The influence of pressure on the reaction shall 

 influence this equilibrium ratio in accordance with the law 

 of mass action, according to which 



"~ = K a constant. 



According to this 



